Sunday

October 4, 2015
Number of results: 109,032

**math**

Hi, How do I improve my math skills? I can't calculate in my head (I.e 2x43), I would actually have to write it down to solve it. I took pre-calc, calc and didnt have problem understanding. I don't know what is wrong. what should I do?
*February 27, 2015 by john*

**Math**

If (a,-3) is a point on the graph of y=x^2+4x, what is the value of a? so far i have -3=x^2+4x i can do the problem on my graphing calc but we can't use a graphing calc on the test so i need to know how to do it by hand. what do i do next?
*January 20, 2010 by Karen*

**Studying for Calc**

I have a quiz on derivatives coming up and I really want to do well, but i'm not sure how to go about studying calc. i have no trouble studying for other subjects, but i'm doing poorly in calc and i need to make some changes in my study habits. any suggestions? i usually work ...
*October 7, 2008 by Elizabeth*

**MATHS**

A CONE WAS CONSTRACTED FROM PLASTIC, HAVE A HEIGHT OF 20cm (PART C). THE LID IS MADE UP OF HEMISPHERE HAVE RADIUS 0F 5cm (PART A) AND PYRAMID HAVE VOLUME OF 81,667cm³. THE LID FITS EXACTLY OVER THE CONE. A) CALC. THE VOL. OF PART A. B) CALC. THE VOL. OF PART C. C) CALC. THE ...
*August 9, 2010 by MTHOMBENI BAFANA*

**Pre-Calc/Calc**

Which set of parametric equations corresponds to this rectangular equation? y=2x-(x^2 / 10) A. x=4t, y=4t-(t^2 /10) B. x=2t, y=8t-(4t^2/10) C. x=2t, y=4t-(4t^2/10) D. x=.5t, y=2t-(t^2/10) E. x=t, y=t-(t^2/10)
*April 17, 2013 by Chris Math Hw Help*

**Calc**

Can someone help me with this calc problem? lim as x->0 (tan^3 (2x))/(x^3)
*January 8, 2009 by Nick*

**help chem!:/**

a) Calc. PH of 0.010 M HF and 0.030 M KF e) calc. PH Zn(OH)2 in wAter
*March 15, 2012 by ALISON*

**Pre Calc**

Does this: sqrt 3x-4=(x-4)^2-3 Multiply out to: x^4-16x^3+90^2-211x+173 I then need to put it in the graphing calc and see what the roots are.
*September 10, 2009 by muffy*

**calculus (limits)**

lim h>0 sqrt(1+h)-1/h not sure how to factor this; not allowed to use L'Hopital's Rule. (that isn't taught at my school until Calc II & I'm in Calc I).
*January 22, 2011 by John*

**C code**

Write a .c file named calc that: - Takes arguments from the command line - Solves a simple math problem - Returns the result as an exit status calc.c: //this is the function that gets called when the executable is run. int main(int argc, char * argv[]){ //I've given you the ...
*February 6, 2013 by Nick*

**Calc or Pre calc**

I am having trouble doing this problem. I know how to do indefinate integrals, but I don't know how to do definate integrals. Can you show me how to do this. Evaluate 5 (x^3-2x)dx 2
*May 14, 2008 by jennifer*

**Pre-Calc**

I'm stuck on a pre-calc problem. I need to find y as a function of x, where the constant c is a positive number for In(y-1)+In(y+1)= -x+c express your question as ln[(y-1)(y+1)] = -x+c change that to exponential form e^(-x+c) = (y-1)(y+1) e^(-x+c) = y^2 - 1 y^2 = e^(-x+c) + 1 ...
*May 9, 2007 by Sarah*

**Pre-Calc**

Can you show me how to find the rectangular equation of r=2costheta + 3 sin theta All I need is an example to work off I was absent today from Pre-Calc and I have homework to do and no explanation with them-Please help with this one Thank you
*October 3, 2011 by Leah*

**chemistry**

liquid heptane C7H16 is completely combusted to produce CO2 and H2O: C7H16 + 11O2 --> 7CO2 + 8H2O the heat combustion for one mole of C7H16 is -4.85*10^-3 CO2 heat of comb. = -393.5 H2O h of c= -285.8 a) calc. the vale of heat of cumbustion for C7H16 in kJ/mol a .0108 mol ...
*March 10, 2010 by hilde*

**math calc.**

Differentiate g(x)=x^(2^1/2)+(x^3/2^1/2)+e^(2^1/2)+(2e^x)^1/2
*July 9, 2008 by nam*

**Math-Calc AB**

e^(-x/2) + xe^(-x/2) = 0 solve for x
*October 14, 2010 by Michelle*

**math/calc**

find y'' if x^4+y^4=16
*February 15, 2012 by angie*

**math pre calc**

solve for x. 8^6+3x=16
*March 25, 2012 by danielle*

**AP Calc B/C**

The base of a solid is the region enclosed by y=x^3 and the x-axis on the interval [0,4]. Cross sections perpendicular to the x-axis are semicircles with diameter in the plain of the base. Write an integral that represents the volume of the solid. I drew a picture, but I ...
*December 15, 2014 by Anon*

**Math Calc**

Find the linear approximation of f(x)=ln x at x=1 where L(x)=
*March 27, 2009 by Manny*

**math (calc 2)**

x+y=3 x-4=-(y-l)^2 rotate about the x-axis
*February 1, 2010 by sally*

**math-calc**

find third derivate f(x)=x/x+1
*February 27, 2011 by shakira*

**math calc**

integral of : x^2 square root of (x-1)
*May 16, 2012 by riss*

**math pre calc**

gaussian elimination x+Y+Z=-2 X-y+5z+22 5x+y+z=-22
*April 25, 2013 by JT*

**math pre calc**

solve for X marticies 2 0 5 4 -1 3 =2 6 x -7
*April 25, 2013 by JT*

**math-calc**

f(x)=(5x-4)e^2x How do you find the one critical number??
*March 13, 2009 by mkcolema*

**math 191- calc**

sect + tan t= (sqr 3)
*April 12, 2010 by krista*

**math-calc**

derivate of 2sin(x)-cos(x)-cot(x)
*February 27, 2011 by shakira*

**MATH, Calc**

P=0.3e^0.08t find the rate of growth.
*September 13, 2012 by Riley*

**Math**

Please someone help with my pre calc question!
*February 11, 2013 by Anthony *

**MATH**

0.4771=x/2.303*8.14[50/323*373 calc.-x?
*May 28, 2015 by tanya*

**math calc!**

find the volume of solid bound by planes x=0 y=0 z=0 and x+y+z=7
*May 9, 2010 by college*

**Pre Calc , Math**

Find the 6 Trig ratios of -7Pie/3
*January 2, 2011 by Joe Daddy*

**Math Calc**

Find the tangent line to the curve (y-x)^2= 2y+4 at the point (2,6)
*August 18, 2011 by Lalee*

**Math**

(1/25)^1/2 i know the answer is 0.02 but how do you find it in a fraction without using a calc?
*September 25, 2011 by Allie*

**Math: Calc: Implicit Derivatives**

Find dy/dx give the relation (x^2/9)+(y^2/16)=1 Thank you!!
*June 14, 2012 by Joey*

**Math(pre-calc)**

what are all the real zeros for 1x^5+2x^4+4x^3+19x^2+9x-5?
*September 27, 2012 by Danii*

**math/calc**

gotta find the first and second derivative of f(x)=x^2/(x-1) thanks for help!
*October 18, 2012 by anon*

**math-calc**

f(x)=3-3x^2 -3 <= x <= 2 How do you find the absolute max and min value? What does x equal?
*March 13, 2009 by mkcolema*

**Math Pre-Calc.**

find the intersection between parabola: y=x^2 + 3x - 4 and line: y=5x + 11
*August 23, 2009 by Soraya*

**math-calc**

function f(x)=3x^2-2x-1 find equation of the line that is tangent and parallel to 8x-2y+12=0
*February 27, 2011 by shakira*

**math**

How do i find X in e^(0.50/x) on a scientific calc? do I use LN, and if so, could you pls tell me how I can plug it in?
*May 31, 2011 by sue*

**Pre-Calc/Math**

Prove the identit: cosxcotx+sinx=cscx
*April 30, 2012 by Yadira*

**Pre-Calc/Math**

If cosx= -2/3 and pi/2, find the exact value of cos(pi/3-x)
*April 30, 2012 by Yadira*

**Pre-Calc/Math**

Prove Identity: (1-cos2x/ tan x) = sin2x
*May 14, 2012 by Yadira*

**Math- Calc**

Find the volume of the solid formed by rotating the region enclosed by y=e^(4x)+2, y=0, x=0, x=0.8
*October 29, 2010 by Kristina*

**Calc**

Profit=p(-p^2+33p+9)-9(-p^2+33p+9)+100 How do I simplify this so I can take the derivative For Further Reading * Calc - Michael, Sunday, November 25, 2007 at 4:17pm Profit=p(-p^2+33p+9)-9(-p^2+33p+9)+100 p(-p^2 + 33p + 9) Just distribute the p in. -9(-p^2 + 33p + 9) Find the ...
*November 25, 2007 by Ben*

**math**

Solve the equation Vx + 7 +5=9 a) -3 b) 9 c) 23 d) 16 V= real number root aka 2nd x2 on graphing calc
*March 17, 2008 by john*

**math calc**

The equation of the tangent line to f(x) =sqrt{x} at x = 25 can be written in the form y = mx+b where m =.1 b =? i don't know how to find the value of b
*March 27, 2009 by Manny*

**Math-alg-calc**

x^(-1/7)=(1/2) Please help the example given was x^(-1/7)=(1/5) so that solved x=78,125. but i have no idea what to do thanks!
*April 5, 2012 by Rochelle F*

**Pre-Calc/Math**

Prove identity: (sec x/csc x) + (sin x/cos x)=(2/cot x)
*May 14, 2012 by Yadira*

**Math ( Pre Calc)**

Find all real and imaginary roots of the polynomial equation 3x^4-x^3+4x^2-2x-4=0
*October 2, 2012 by Ains*

**What is discrete math? And is it relatively easy?**

I ask because my TA recommended taking it next semester along with calc 3. My major is electrical engineering, and I might throw actuarial science into the mix too. So yeah, lots of math.
*December 18, 2007 by Jake*

**Math-Calc**

The lim as x goes to 0- for cos(x)/sin(x). I know the answer is negative infinity but I don't really understand why.
*June 8, 2011 by Marissa*

**math/Calc**

g(x)={1+cos(pi/2-x/1) 0 for-2 <or= x <or=2 for x<2 or x>2 is g(x) continuous at x=2 is it differentiable at x=2? ex[lain in detail I'm very confused as to how to solve this problem
*February 9, 2012 by angie*

**Pre-Calc/Math**

Given cos x=2/3 and 3pi/2<x<2pi, find the exact value of cos2x?
*April 30, 2012 by Yadira*

**Math, Pre Calc**

Given that (+-2) and i are the roots of a 4th degree polynomical, find the equation. Please help! Thank you:)
*September 5, 2012 by Nikki*

**physics**

an aeroplane is travelling horizontally at a speed of 80ms and drops a crate of emergency supplies.To avoid damage,the max vertical speed of the crate on landing is 20ms. a)calc d max height of the aeroplane when the crate is dropped b)calc d time taken for the crate to reach ...
*January 19, 2012 by Shanti*

**math-calc**

show that 1-(x/2) is the tangent line approximation to 1/sq rt(1+x) near x=0 i know the formula for apprx. is y = f(a)+f'(a)(x-a) but i don't understand how to work backwards to get this.
*October 19, 2008 by joe*

**Calc pt2**

Original question: Posted by Lost One on Tuesday, March 5, 2013 at 12:04pm. Let f(x) = (2/3)x^3 - 2x + 1 with a restricted domain of [1,infinity]. What is the value of (f-1)'(x) when x = 13? •Calc - Steve, Tuesday, March 5, 2013 at 12:58pm since x = f^-1(y) and dx/dy = 1/y' f...
*March 5, 2013 by Lost One*

**calc**

Use L’Hopital’s rule to find the limit of this sequence (n^100)/(e^n) ...If you do L'Hop. Rule it would take forever, right? You would always get an (e^n) at the bottom and will have to use the L'Hop. rule 100 times to find the limit...100*n^99, 9900n^98, and etc. Is there a ...
*February 1, 2012 by lola*

**Math/calc**

an electric current I , in amps is given by: I= cos(wt) + sqrt of 3 sin(wt) where w is positive constant. what are the max and minimum values of I?
*March 30, 2010 by Jolly :)*

**Math(Pre=Calc)**

The first term in a sequence of number is t1 = 4. The terms that follow are defined by the formula: tn - tn-1 = 3n -2. Determine the value of t50.
*July 6, 2011 by Kate*

**Math- AP Calc **

If 3x+xy+4y=8, what is the value of d^2y/dx^2 at the point (1,1)? My work: 3+(x)(dy/dx)+(y)+4(dy/dx)=0 dy/dx(x+4)=-3-y dy/dx=-3-y/x+4 2nd Dervative: (x+4)(0-dy/dx)-(-3-y)/(x+4)^2 (x+4)(-(-y-3/x+4))-(-3-y)/(x+4)^2 (x+4)(y+3)/(-x+4)+(y+3)/(x+4)^2 *Mult. everything by (-x+4) ...
*October 6, 2014 by David*

**Pre-Calc**

This is the last question on my pre-calc homework, I looked through the textbook and have no idea how to do this. Use the Law of Sines to solve for all possible triangles that satisfy the given conditions. (If an answer does not exist, enter DNE. Round your answers to one ...
*March 5, 2015 by Cat Jones*

**Math Pre-Calc.**

Determine the domain and range of y= (radical) x-4 y= (radical) x^2-4 plz help me step by step. I just need to refreash my math, but i forgot how to find it
*August 23, 2009 by Soraya*

**math calc**

using geometry, calculate volume of solid under z= square root of 49-x^2-y^2 and over circular disk x^2+y^2 is less than or equal to 49
*May 9, 2010 by college*

**Math**

Express the following number in scientific notation: 23^941 How do i get the answer for this? on my graphing calc, i get an error overflow messasge when i try to compute it. THANK YOU!!!!!
*March 11, 2012 by Sandy*

**Math: Calc 2**

Find the volume of the solid obtained by rotating the region under the graph of the function f(x) = x^(13/12) about the x-axis over the interval [1,3]. Thanks!
*July 9, 2013 by James*

**Pre-Calc/Math**

Use factoring, the quadratic formula, or identities to solve cos(x)+1=sin^(2)x. Find all solutions on the interval [0, 2pi)
*May 23, 2012 by Yadira*

**Math Pre Calc Help**

(cos^4x -sin ^4 x)/(sin^2x)=cot^2x -1 How to prove true?
*November 10, 2014 by Anonymous*

**math**

evaluate: cos (arc sin (4/5) - arc tan 2) with out using a calc.
*April 15, 2010 by krista*

**Math: Calc**

y= 3x^2+3x+2 Find the diferential dy when x=4 and dx = 0.4 and when dx = 0.8. How do I find these diferentials? y= 3x^2+3x+2 dy= 6x dx + 3dx Now put in the values, and compute.
*November 16, 2006 by Katie*

**math (pre-calc)**

Solve for x: 1. 3^2x+3^x+1-4=0 2. log3(x=12)+log3(x+4)=2 3. lnx+ln(x+2)=4 4. 3*4^x+4*2^x+8=0
*April 18, 2010 by Rony*

**Math AP Calc**

The population of New Hampshire was 1 million in 1990. It doubles every 25 years. Estimate the population in 1996.
*August 29, 2010 by Leanna*

**Differential Calc (Math)**

Stuck... can't seem to use l'hopitals, nor can I use logrithmic differentiation... lim (e^(2x)+ x)^(1/3x) x->0+ Thank you so much
*December 13, 2012 by Joey*

**Math (Pre-Calc)**

Find all the solutions of the equation in the interval {o,2pi) 5sqrt3 tan x+3=8sqrt3 tan x
*February 8, 2015 by Fiona*

**pre calc math**

need to solve the first five terms recursively. Can do the other four once I get the first one. a[n]=a[n-1]/2 and a[1]=-8
*May 19, 2010 by Ken*

**Math- Calc**

Sketch the region enclosed by the given curves. Decide whether to integrate with respect to x or y. Then find the area of the region. y=e^(4x), y=e^(6x), x=1
*October 29, 2010 by Kristina*

**math (pre calc)**

4cot^2x-4/tanx+cosxsecx write expression in factored form as an algebraic expression of a singletrig function
*April 26, 2011 by josh*

**math/calc**

How do I solve for an area under the curve when y = x^2 and solve for above the interval (1,2) ? Any resources where I could see examples would be helpful. Thanks!
*July 18, 2012 by cathy*

**math- pre calc/trig**

Find the length of each side of a square if the diagonal is 7(square root 2)? How do I solve or set up this problem?
*September 30, 2014 by jen*

**Math (Calc)**

Find the Exact value of Pi/24. I'm not sure whether to use a half-angle formula or a difference/sum of angles formula.
*December 9, 2007 by Bryan*

**Math - Pre-Calc**

So far I got it down to ((4/3)n^3+(11/6)n^2)/((4/3)n^3)+(2n^2)+(2/3)n). Would I be able to cancel out the ((4/3)n^3)s? So that it would be ((11/6)n^2)/((2n^2)+((2/3)n))? Or can I simplify that even futher by combining the (n^2)s?
*April 13, 2009 by Katie*

**Math Calc**

Given a right triangle ABC with a=13 and b=26, find the value of angle A, angle B, and side length c. Round to the nearest thousandth.
*November 2, 2014 by Johnny*

**math, calc 2**

Using the disk method, find the volume of a right circular cone with height h and base radius r. I know the answer is 1/3pier^2h, but how do you explain or work out the problem?
*January 17, 2007 by George*

**Math Calc 1 Last question **

Find the volume of the solid obtained by rotating the region bounded by the curves y=4x-x^2, y=8x-2x^2 about the line x=-2. I got 256 pi/3 but pretty sure my work is wrong.
*December 12, 2012 by Anonymous*

**AP Calc**

When a chain hangs under its own weight, its shape is catenary. The equation of a catenary with a vertex on the y-axis is y=e^x+e^-x. Find the length of the chain from x=-2 to x=2. Then use the same technique from Problem #8(Previous AP calc problem I posted) to find the ...
*July 31, 2014 by Anon*

**math**

One of the following functions is neither odd nor even. Which one? x^5 + 3x 6x^2 – |x^2| + 3 x^9 + 3x^7 + 6x (my answer)x^2 + 3x + 3 + |x –3| This is really tricky pre-calc graphing problem. Thanks for the help!
*October 1, 2012 by Anonymous*

**math-calc**

A rectangle is inscribed with its base on the x-axis and its upper corners on the parabola y+1-x^2. What are the dimensions of such a rectangle with the greatest possible area? width? height?
*March 13, 2009 by mkcolema*

**Calc**

A student is in a 20 week calc class. The function f(t)=50-50e^0.2t f(t) measures the students problem speed in t weeks -how many problems per hour can a student solve at the beginning of the course - how many problems per hour can a student solve halfway through the course -...
*July 20, 2012 by Marshall*

**math**

ok so i havent done domain and ranges for a while so i need some help this is just a generic question but i want to make sure i know how to do them before starting calc so can someone please explain how i would heres a function f( t) = t+ 3 /(t2 – 5t – 66),
*August 24, 2012 by kieran*

**math 234 calc 4 !!!!!!!!!!!**

write this function in terms of heaviside functions, and then show your work in finding its laplace transform f(t)= o if o < t<3 t-3 if 3lessthan or equal <lessthan or equal to t < 6 o if 6< t < infinity
*April 12, 2011 by john *

**Math (Calc)**

Find all solutions to the following equation on the interval 0<=x<=2PI 8cos^2(X)sin^2(X) + 2cos^2(X) - 3 = 0 There are 8 solutions. If somebody could show me how to do it and not give me the answers, that would be great.
*December 9, 2007 by Bryan*

**math**

1.) What is the square of âˆš10? 2.) Find tan 14. 3.) Find cos 45. some one told me to use a scientific calculator and it would give me the answer but i can't find my calc.
*June 12, 2010 by Unknown*

**calc**

f(x)=7x-4 a) f(0) b) f(-3) c) f(b) d) f(x-1)
*October 4, 2009 by kim*

**calc 2**

(dy/dx) + 8y =5
*March 24, 2010 by Anonymous*

**calc 2**

(dy/dx) + 8y =5
*March 24, 2010 by Anonymous*

**calc 2**

(dy/dx) + 8y =5
*March 24, 2010 by Anonymous*

**calc 2**

(dy/dx) + 8y =5
*March 24, 2010 by Anonymous*