Saturday

November 28, 2015
Total # Posts: 439

**Conjecture**

what conjecture could be made and proven from the following? sin(3x)/sin(x) - cos(3x)/cos(x) I put it on my calculator and based on the graph I say that as it crosses the y axis the values get larger.
*November 14, 2012*

**Difficult Trig Word Problem**

sorry y(t) =4e(then the exponent -3t) all times sin(2pi*t)
*November 14, 2012*

**Difficult Trig Word Problem**

The displacement of a spring vibrating in damped harmonic motion is given by y(t) = 4e^-3t sin(2pi*t) where y = displacement and t = time with t greater than/equal to zero. Find the time(s) when the spring is at its equilibrium position (y=0). The number "e" is Euler...
*November 14, 2012*

**Precalculus 2**

Similiarly to a question I asked previously I took the same approach. the problem is: what value(s) of theta solve the following equation? cos(theta)sin(theta) - 2 cos(theta) = 0? I let Cos theta = X and sin theta = X unfortunately I end up with something completely odd. Can ...
*November 14, 2012*

**Triangles**

solve any triangles satisfying alpha = 20 degrees b = 10 c = 16 b and c are 2 side values and if I use the pythagorean theorem and I get 18.18? Did I do this right?
*November 14, 2012*

**Trigonometry**

What value(s) of theta solve the following equation? cos^2(theta)-cos(theta)-6=0? I try plugging in different numbers but I am not sure exactly what I am looking for in order to solve?
*November 14, 2012*

**Precalculus**

Sorry but I meant to say LS = cos^2x-sin^2y
*November 14, 2012*

**Precalculus**

Prove or disprove cos(x+y)cos(x-y)=cos squared (x) - Sin squared (x) I dstributed the cosines and attempted to cancel out terms but I can't get the signs right. Any help on what I am missing?
*November 14, 2012*

**Physics**

A certain light truck can go around a flat curve having a radius of 150 m with a maximum speed of 29.0 m/s. With what maximum speed can it go around a curve having a radius of 88.0 m?
*November 13, 2012*

**Physics**

An air puck of mass 0.23 kg is tied to a string and allowed to revolve in a circle of radius 1.0 m on a frictionless horizontal table. The other end of the string passes through a hole in the center of the table, and a mass of 0.9 kg is tied to it. The suspended mass remains ...
*November 13, 2012*

**Physics**

A race car starts from rest on a circular track of radius 445 m. The car's speed increases at the constant rate of 0.380 m/s2. At the point where the magnitudes of the centripetal and tangential accelerations are equal, find the following. (a) the speed of the race car (b...
*November 13, 2012*

**Physics**

A rotating wheel requires 8.00 s to rotate 29.0 revolutions. Its angular velocity at the end of the 8.00 s interval is 95.0 rad/s. What is the constant angular acceleration of the wheel? (Do not assume that the wheel starts at rest.)
*November 13, 2012*

**Precalc/Triangles**

Draw and solve any triangles satisfying alpha = 29 degrees a = 7 c = 14 I realize I need to draw a non-right triangle and label the sides but I am completely confused one what to do after I draw the triangle
*November 13, 2012*

**Physics**

A 7.45-g bullet is moving horizontally with a velocity of +348 m/s, where the sign + indicates that it is moving to the right (see part a of the drawing). The bullet is approaching two blocks resting on a horizontal frictionless surface. Air resistance is negligible. The ...
*November 5, 2012*

**phisics**

A 7.45-g bullet is moving horizontally with a velocity of +348 m/s, where the sign + indicates that it is moving to the right (see part a of the drawing). The bullet is approaching two blocks resting on a horizontal frictionless surface. Air resistance is negligible. The ...
*November 4, 2012*

**Programming-Array**

If i have a string with a word 'today' in it. If a user inputs a char (lets say b). how do I right the array to make it see if the char "b" is in the string today. LOOP??? int i; for(i=0; i<SIZE; i++) { guessedChar[i]; /*or*/ wordString[i]; }
*November 1, 2012*

**Programming**

int a = 10; int b = 5; int total = 0; printf("%d + %d = %d\n", a, b, total); printf("%d - %d = %d\n", a, b, total); printf("%d * %d = %d\n", a, b, total); printf("%d / %d = %d\n", a, b, total); /*Without an array*/ if(var == 1) { return ...
*October 30, 2012*

**phisics**

The drawing shows two boxes resting on frictionless ramps. One box is relatively light and sits on a steep ramp. The other box is heavier and rests on a ramp that is less steep. The boxes are released from rest at A and allowed to slide down the ramps. The two boxes have ...
*October 28, 2012*

**C programming**

I'll help you but I'm not gonna right your code for you. What are you lost on?
*October 26, 2012*

**Computers**

carpel tunnel syndrome? is that what your asking?
*October 23, 2012*

**phi 103**

"If that wasn't illegal, then it wouldn't be against the law" may commit which fallacy?
*October 23, 2012*

**phisics**

The drawing shows two boxes resting on frictionless ramps. One box is relatively light and sits on a steep ramp. The other box is heavier and rests on a ramp that is less steep. The boxes are released from rest at A and allowed to slide down the ramps. The two boxes have masse
*October 21, 2012*

**Calculus L'Hopital Rule**

lim x->0 (x)sin(x)/1-cos(x). They both go to 0 so 0/0. now take L'H and product rule of top? lim x->0 (1)sin(x)+ cos(x)(x)/1-cos(x) what next? how do i solve from here?
*October 18, 2012*

**Calculus**

f(4)= 4^4 e^-4 = 4.6888
*October 18, 2012*

**Calculus**

f(x)=x^4e^-x f(0)=0^4e^0 = 0 f(-4)=-4^4e^4 = 13977.13 I feel like i didnt do that right. It seems like a weird number for a critcal point.
*October 18, 2012*

**Calculus**

Sub 0 and -4 into f(x). or f'(x)?
*October 18, 2012*

**Calculus**

Would the derivative be e^-x (x^4-4x^3)?
*October 18, 2012*

**Calculus**

Find the critical points of f(x)=x^4e^-x. You would use the product rule. Then what?
*October 18, 2012*

**Calculus**

The side of a square box is increasing at a rate of 4mm/s and its height is increasing at a rate of 2mm/s. How fast is the volume increasing when the side is 40mm and the height is 100mm. Can someone just tell me what formula to use?
*October 18, 2012*

**Calculus**

y=sqrt(x)^1/x. Find dy/dx That is to the power of 1/x So to start this do I need to take Ln on both sides and then use a logarithm property? Ln(y)=lnx^1/2x?
*October 15, 2012*

**chem**

The complete combustion of 1.283g of cinnamaldeyde (C9H8O, one of the compounds in cinnamon) in a bomb calorimeter (Ccalorimeter=3.841 kJ/C) produced an increase in temperature of 130.32 C. Calculate the molar enthalpy of combustion of cinnamaldehydy (delta H comb) (in ...
*October 15, 2012*

**chemistry**

how would you separate a mixture of NaCl, Fe pellets and water
*October 14, 2012*

**chemistry**

how would you separate a mixture of NaCl, Fe pellets and water
*October 14, 2012*

**Chemistry**

Complete the electron dot structure below to show how beryllium flouride (BeF2) is formed. F F Be+ -> Be F F
*October 9, 2012*

**Chemistry**

What is the coordination number of the ions in a face-centered cubic crystal? In a simple cubic crystal?
*October 9, 2012*

**Chemistry**

Write the symbol and electron configuration for each ion and name the noble gas with the same configuration. a. nitride _________________________ b. oxide ___________________________ c. sulfide _________________________ d. bromide _________________________
*October 9, 2012*

**Chemistry**

How many electrons will each element gain in forming an ion? a. Nitrogen ______ b. Oxygen ________ c. Sulfur _______ d. bromine _______
*October 9, 2012*

**Chemistry**

Why do beryllium and flouine combine in a 1:2 ratio?
*October 9, 2012*

**Chemistry**

Complete the electron dot structure below to show how beryllium flouride (BeF2) is formed. F F Be+ -> Be F F
*October 9, 2012*

**Precalc/Trig Word Problem**

From the top of a 200-ft lighthouse, the angle of depression to a ship in the ocean is 23 degrees. How far is the ship from the base of the lighthouse?
*October 8, 2012*

**Word Problem**

In a certain individual the resting diastolic pressure at time t is given by B(t)= 80+7sin((pi)(t)/(12)) where t is measured in hours since midnight and B(t) in mmHg (millimeters of mercury). Find this person's pressure at 6:00 am, 10:30 am, noon, and 8:00 pm.
*October 8, 2012*

**Precalculus/Trig 6**

Find the exact value of the following trigonometric functions: sin(13pi), cos(14pi), tan(15pi)
*October 8, 2012*

**Precalculus/Trig 5**

Find the exact value of thet following trigonometric functions: tan(5pi/6) tan(7pi/6) tan(11pi/6)
*October 8, 2012*

**Precalculus/Trig 3**

The degree measure of an angle theta is 40 degrees. What is the radian Measure of theta? at what point P does the terminal ray intersect the unit circle (what is the ordered paid P(____, ___)?
*October 8, 2012*

**Precalc/Trig 2**

The point P lies in the 4th quadrant and is located on a circle of radius 2. Find the missing coordinate for P. (___, (negative square root of 3)).
*October 8, 2012*

**Precalc/Trig 1**

What equation would you use to show that the point ((square root of 11)/(6), (5/6))is on the unit circle?
*October 8, 2012*

**math**

65 men 75 women are enfolled in calculus. There are 30 business majors, 40 biology majors, 50 computer science majors, and 20 mathematics majors. No person has a double. If a single calculus student is chosen, find the probability that that the student is not a mathematics major
*September 28, 2012*

**Physics**

A ball is thrown downward at 12.3 m/s. How much time does it take for it to reach the ground, 182.6 m below?
*September 25, 2012*

**Physics**

A student drops a rock off a bridge. The rock has a mass of 5.81 kg. If the bridge is 48.7 m high, how much time does it take it to reach the water below?
*September 25, 2012*

**Math**

What compound polygon has 28cm and area 48 cm
*September 25, 2012*

**Precalculus SOH CAH **

how are the following relations true? S(theta + pi/2) = C(theta) and C(theta + pi/2) = -S(theta)?
*September 22, 2012*

**math**

You do 14500 times .09 then you add that to 14500 to get year 1 then repeat that till you get 22309.51.or something close to that.
*September 19, 2012*

**Derivatives (check answer)**

Let y=x^5 - pi^5. Find dy/dx My answer is 5x^4 because pi^5 becomes 0? Am I correct?
*September 17, 2012*

**Algebra (Please check)**

Number 1 I know is D
*September 17, 2012*

**Algebra (Please check)**

PLEASE CHECK MY ANSWERS (: I just want to make sure I am doing this correctly __________________________________ Graph the system of constraints and find the value of x and y that maximize the objective function. Constraints: x ≥ 0 y ≥ 0 y ≤ (1)/(5) x + 2 5...
*September 17, 2012*

**Algebra (Need help desperately)**

Thanks :D I'm 90% sure number 1 is D, but do a good way how I could do 2 or 3? If you dont mind explaining to me?
*September 17, 2012*

**Precalculus **

he distance between 2 points (x1,Y1) and (x2,y2) is given by d = square root (x1-x2)^2 + (y1-y2)^2 a - pick 2 arbitrary points in 3 dimensions, (x1, y1, and Z1) and (x2,y2,z2) and plot these points. Not that there are 90 degrees between the xy, xz, and yz axes. b- using your ...
*September 14, 2012*

**Precalculus**

The distance between 2 points (z1,Y1) and (x2,y2) is given by d = square root (x1-x2)+ (y1-y2)^2) a - pick 2 arbitrary points in 3 dimensions, (x1, y1, and Z1) and (x2,y2,z2) and plot these points. Not that there are 0- degrees between the xy, xz, and yz axes. b- using your ...
*September 14, 2012*

**Calculus (Check)**

This seems to easy. Check please. Find. Lim (x^2)-4 x->2 e I substitute in 2 (2^2)-4 e gives me 4-4 e So my answer is e^0 or 1.
*September 14, 2012*

**Calculus with Analytical geometry**

I'm stumped on this one. lim |x-1|sin(1/x-1) x->1
*September 14, 2012*

**Calculus**

Thank you, I see where I made my error now. X^2 over x^2 becomes 1. I cancelled them out.
*September 14, 2012*

**Calculus **

Check my work please? Determine if f(x)= (x^2-3x+2)/(1+x^2) has a horizontal asymptotes. If so, give the equation. So I took x^2 and divided everything by it. (x^2/x^2)-(3x/x^2)+(2/x^2) / (1/x^2)+(x^2/x^2) Cancelled out some x's and have -(3/x)+(2/x^2) / (1/x^2) Now as x ...
*September 14, 2012*

**Precalculus**

how are the following relations true? S(theta + pi/2) = C(theta) and C(theta + pi/2) = -S(theta)?
*September 10, 2012*

**Precalculus**

Find the distance along an arc on the surface of the earth that subtends a central angle of 1 minute. (1 minute = 1/60 degree) This is a nautical mile. Note that the radius of the Earth is 3960 miles and there are 1760 yards in a mile. Express your answer in both miles and yards.
*September 10, 2012*

**Chem I**

Ammonia is composed of H and N in a ratio of 9.33g N to 2.00g H. If 4.56g N combine completely with H to form ammonia, how many grams of ammonia would be formed? How do you calculate this?
*September 2, 2012*

**Chemistry**

Calculate the mole fraction of glucose (C6H12O6) in a solution which contains 15g of glucose in 100 g of H2O.
*July 31, 2012*

**Chemistry**

For the reaction IO3– + 5I– + 6H+ 3I2 + 3H2O the rate of disappearance of I– at a particular time and concentration is 2.8 x 10-3 M s-1. What is the rate of appearance of I2 in molarity per second?
*July 31, 2012*

**Chemistry**

A buffer is prepared by transferring equal concentrations of the components of the conjugate pair, C6H5COOH and C6H5COONa, into a beaker. What is the approximate pH of the buffer? (Ka = 6.5 10–5) a) 2.81 b) 4.19 c) 7.00 d) 9.81 e) 11.19
*July 31, 2012*

**Chemistry**

how does a formula of Iron(III) and ethylenediamine, assuming a coordination number of 6 look and what is it's name and written transition metal formula
*July 29, 2012*

**Chemistry**

how does a fomula of Iron(III) and ethylenediamine, assuming a coordination number of 6 look and what is it's name?
*July 29, 2012*

**Chemistry**

Ammonia is a stronger ligand than is the chloride ion. What does this statement mean?
*July 29, 2012*

**Math**

A square is made up of section A and section B. Section A is 500 sq. ft. and section B is 750 sq. ft. What percent of the square is section A?
*June 9, 2012*

**chemistry**

Calculate the solubility of Cacl2 in g/L based on the experiement. Given 650g of CaCl2 added to 1.0L and allowed to dissolve as much as possible. While the remaining solid CaCl2 is filtered out of the solution and found to have a mass of 5.509g. What is the solublity of CaCl2
*June 6, 2012*

**trig**

y=92.5 x=157.9 x+y=250.4ft
*June 5, 2012*

**ALG 2 (exponents)**

Write log'2' 8 = 3 in exponential form?
*May 12, 2012*

**Algebra 2**

How would I find the sum of the geometric series given? 1/5 - 1/25 + 1/125
*May 12, 2012*

**Math**

You need to line the inside of a tank that is 6 ft. diameter and 40 ft. high. You are going to line only the sides with the lining. How many sq. ft. are needed?
*May 4, 2012*

**Chemistry**

How much heat is either ______(absorbed or given off) when 91.45g of HI decomposes to H2 and I2 at 25 degrees C? What goes in the blank and how much heat? Thanks!
*April 29, 2012*

**Algebra 2 (Geometric Series)**

Write (2x+3y)^3 in expanded form I need a little help as far as how I would begin working this problem out.
*April 26, 2012*

**Algebra 2 **

Find the inverse of the following function: f(x) = 3x + 12 I don't think I worked this problem off correctly...I am suppose to find the inverse of the function Is this the correct way to work this problem? y= 3x + 12 x= 3y + 12 3y = x - 12 f-1(x) = x - 12/3
*April 18, 2012*

**Algebra 2 (Quadratic Equations)**

Is the point (-3, -2) a solution of the intersection of the following set of quadratic equations: Y < -X^2 X^2 + Y^2 < 16 I'm not sure how to actually work this problem out. Can anyone help me with this problem please.
*April 18, 2012*

**Geometric Series (Algebra 2)**

Thank you Damon, that helped alot...
*April 14, 2012*

**Geometric Series (Algebra 2)**

I need some assistance or a formula when trying to find the first term of geometric series please! I don't understand this!!!! What is the first term of a geometric series with a summation of 289, 5 terms and a common ratio of 1/2?
*April 14, 2012*

**Algebra 2**

Thank you, I think I understand how to work it out now! That helped me out so much!
*April 12, 2012*

**Algebra 2**

What is the first term of a geometric series with a summation of 800, 4 terms and a common ratio of 3?
*April 12, 2012*

**Algebra 2**

What is the first term of a geometric series with a summation of 800, 4 terms and a common ratio of 3?
*April 11, 2012*

**government**

idk what this stuff is im doing it on germany
*April 11, 2012*

**government**

Using the Internet, encyclopedia, and/other reference material for research, write a 1,000-word report on feudalism in the history in one of the following countries: •France •England •Germany Include the approximate years when feudalism began and ended in that ...
*April 11, 2012*

**physics**

A pair of eyeglass frames are made of an epoxy plastic (coefficient of linear expansion = 1.30 10-4°C−1). At room temperature (20.0°C), the frames have circular lens holes 2.27 cm in radius. To what temperature must the frames be heated if lenses 2.28 cm in ...
*April 11, 2012*

**physics**

A hypodermic syringe contains a medicine with the density of water (figure below). The barrel of the syringe has a cross-sectional area of 2.44 10-5 m2. In the absence of a force on the plunger, the pressure everywhere is 1.00 atm. A force vector F of magnitude 1.91 N is ...
*March 28, 2012*

**physics**

For safety in climbing, a mountaineer uses a nylon rope that is 65 m long and 1.1 cm in diameter. When supporting a 94-kg climber, the rope elongates 1.4 m. Find its Young's modulus.
*March 28, 2012*

**physical aspects of nature**

A 1,440-N crate is being pushed across a level floor at a constant speed by a force of 250 N at an angle of 20.0° below the horizontal; (a) What is the coefficient of kinetic friction between the crate and the floor? (b) If the 250-N force is instead pulling the block at ...
*March 15, 2012*

**Math**

A swimming pool is 40 feet long, 20 feet wide, 8 feet deep at the deep end, and 3 feet deep at the shallow end; the bottom is rectangular. If the pool is filled by pumping water into it at the rate of 40 cubic feet per minute, how fast is the water level rising when it is 3 ...
*March 2, 2012*

**perimeter problems math**

36
*February 21, 2012*

**Economics**

Wilpen Company, a price- setting firm, produces nearly 80 percent of all tennis balls purchased in the United States. Wilpen estimates the U. S. demand for its tennis balls by using the following linear specification: where Q is the number of cans of tennis balls sold ...
*February 19, 2012*

**chemistry**

KI+H2SO4+KIO3 Write the balanced net ionic equation.
*February 18, 2012*

**Algebra 2**

How did you come up with that answer, I would like to learn how to work it out.
*January 17, 2012*

**Physics (verification)2**

I would love for someone to please verify my solution for this problem: A former amusement park attraction consisted of a huge vertical cylinder rotating rapidly around its axis. The rotation speed should be sufficient for the people found inside to be stuck to the wall when ...
*December 10, 2011*

**Physics (verification)**

I would love for someone to please verify my solution for this problem: A former amusement park attraction consisted of a huge vertical cylinder rotating rapidly around its axis. The rotation speed should be sufficient for the people found inside to be stuck to the wall when ...
*December 9, 2011*

**physics**

my bad, drwls is right, didn't take for account that it's around the rink, so there's the centripetal acceleration to take for account
*December 9, 2011*