Post a New Question

Posts by steve

Total # Posts: 50,569

physics
correct

physics
T^2 is proportional to L/g. The mass has no effect. So, if A^2 = L/g B^2 = 2L/g B^2/A^2 = 2 B/A = ?2 ? 1.4 answer C

physics
Since the period T = 2??(m/k) y = 0.1 sin(?(k/m) t) = 0.1 sin(5t) the speed v = 0.5 cos(5t) which has a maximum value of 0.5

Math
4 6/12 - 3 8/12 = 3 18/12 - 3 8/12 = 10/12 so, 10" left or, 54"-44" = 10"

Math help plz
the area needed is ?r^2 + 2?rh = ?r(2h+r) = 6?(24+6) = 180? = 565

Math
#14 wants volume, not area the others look good.

math
For #1 and 2, type in your function at wolframalpha.com or any of many other fine graphing web sites. -4 = 4-8 7 = -4+11 so, (x,y) -> (x-8,y+11)

Pre calc
because I studied the double-angle formulas, as you need to do!

Pre calc
In QI, you have sinx = 5/13 cosx = 12/13 tanx = 5/12 sin2x = 2sinx cosx = 2(5/13)(12/13) = 120/169 similarly using the other double-angle formulas.

Pre calc
If this isn't even math to you, you clearly haven't been paying attention during the discussion of the double-angle formulas ... (1-cos2x)/sin2x = (1-(2cos^2x-1))/(2sinx cosx) = (2-2cos^2x)/(2sinx cosx) = 2sin^2x/(2sinx cosx) = sinx/cosx = tanx sin4x/sinx = (2sin2x ...

Urgent math help!!
Huh? You are in trig, and cannot tell what the x- and y- coordinates are? The point (-3,4) is at x = -3 y = 4 since r^2=x^2+y^2, r=5. sin? = y/r = 4/5 You got the right answer; was it just a guess?

Urgent math help!!
Draw your triangle in standard position. It is clearly a 3-4-5 right triangle. sin? = y/r

Trig
well, csc^2x-1 = cot^2x cot*cos/cot^2 = cos/sin * cos * sin^2/cos^2 = sin

Math
she kept 3/8 * 25 = ? kg

Math
you have to keep writing an equation; you just dropped off the right side. In any case, remember from your Algebra I that you usually need to set stuff to zero to solve. Now, using the fact that sin^2x+cos^2x=1, 2cos^2x+sinx-1 = 0 2-2sin^2x + sinx-1 = 0 2sin^2x-sinx-1 = 0 (...

Trig
oops, sorry Reiny...

Trig
Remember your double-angle formulas. You have tan(2*30) = ?3 Reiny dropped the 2 in the numerator...

Trig
(1+tan^2x)/tan^2x = 1/tan^2x + 1 = cot^2x + 1 = csc^2x

laplace transformation:help damon or steve or rein
In case you don't have an online calculator handy, L{1} = 1/s L{e^t} = 1/(s-1) = F(s) L{t^2 e^t} = (-1)^2 F"(s) = 2/(s-1)^3 L{y} = f(s) L{y'} = sf(s)-f(0) = sf(s)-1 L{y"} = s^2f(s)-sf(0)-f'(0) = s^2f(s)-s+2 L{y'"} = s^3f(s)-s^2f(0)-sf'(0)-f&...

Bachelor of computer science
I'm sure you can do the I/O. The calculation is if hours <= 0   print "error - no hours entered" else if hours <= 40    pay = rate * hours else   pay = rate*40 + rate*1.5*(hours-40) endif

math
make up your mind -- BASIC or FORTRAN ? in any case, find the prime factors of each number, and select all those common to both. Their product is the HCF.

algebra
I don't see an inequality either. But, since the cost is not zero, you know that profit < earnings

MAth
If x is the middle integer, (x+4)/(x-4) = 2

Calc
yes. The f"' nonzero makes sure that it's not just a cup like x^4.

Calc
the slope has a minimum at x=c. f"(c)=0 means it's an inflection point. Think of the graph f(x) = x^3

Math
suppose k" = -5 on [-3,0]. You know that k'(-2) = -4. So, k'(0) would be -4+2(-5) = -14 Now, suppose that k" = -2 on [-3,0]. k' would be -4+2(-2) = -8 So, -14 <= k'(0) <= -8 remember that k" is just the slope of k'. k'(0) will lie ...

Math
you have ?y ? k'(-2)*?x You have k(-2), so use ?x=0.6 If the curve is concave down, it lies below the tangent line.

Math
6x10^-5 * 700 = (6*7)x10^(-5+2) = 42x10^-3 4x10^5 * 1.5x10^7 = (4*1.5)x10^(5+7) = 6x10^12 Now just divide as usual

math
just solve the system a(r^5-1)/(r-1) = 61 ar^4 = 81 Hint: 81 = 3^4

math
draw a diagram. Using similar triangles, h/(9+6) = 5/6

MATH
there are 20 students. So, the chance of getting the two freshmen is 2/20 * 1/19 = 1/190 This just selection without replacement.

Precalculus
the only constant I see is -1/5 I guess that make the power clear, eh?

proofread
I'll let bob handle the physics. You need to proofread your post this time -- get rid of the sloppy typos and finish the question.

science URGENT!!
hello. amplitude is wave height...

science URGENT!!
wave height is amplitude. and it still does not affect the frequency or the speed!

Science
F = ma, so a = -144/15 = -9.6 m/s^2 75 mi/hr = 33.53 m/s v = Vo + at = 33.53 - 9.6t v=0 at t=3.49 So, it will take 1.6 + 3.49 = 5.09 seconds to stop No deceleration occurs during the first 1.6 seconds, so the distance is s = 33.53*5.09 - 4.9*3.49^2 = 110.99 m

Science. HELP!!
not at all. The speed of light does not change because of the color. The speed of sound does not change because the pitch changes.

Math
The first step is to remove the parentheses. Then what do you have?

SCIENCE
The key to this is to come up with the equation of motion. If you review the relevant section, you will easily see that h(t) = 70+40t-4.9t^2 v(t) = 40-9.8t Now just apply your skills from Algebra I to find the vertex and find h(t)=70 and v(10)

Math1
just as the last one, 50=7*7+1

Math1
yep, it's a trinomial. If you want to factor it, recall that 15 = 2*7+1

math
without parentheses, exponents are done first. Remember PEMDAS? Parentheses, exponents, mult/div, add/sub So, -4^2 is evaluated as -(4^2) If you want +16, then that is (-4)^2

math
8×5-(6+12)÷6 = 37 as for simplifying, it doesn't get much simpler than 37 ...

Science, Physics
        sinx(cosx-sinx) ---------------------------------- sinx(cosx+sinx)(cosx-sinx)

Science, Physics
      sinx(cosx-sinx) ----------------------------- sinx(cosx+sinx)(cosx-sinx)

Science, Physics
(e2x)1/x < (x+ex+e2x)1/x < (2e2x)1/x e2 < (x+ex+e2x)1/x < 21/xe2 Now take the limits, and since 21/x-> 1, e2 < (x+ex+e2x)1/x < e2 so (x+ex+e2x)1/x = e2

Science, Physics
(e2x)1/x < (x+ex+e2x)1/x < (2e2x)1/x e2 < (x+ex+e2x)1/x < 21/xe2

Science, Physics
(e2x)1/x < (x+ex+e2x)1/x < (2e2x)1/x e(2 < (x+ex+e2x)1/x < 21/xe21/x

Science, Physics
(e2x)1/x < (x+ex+e2x)1/x < (2e2x)1/x

math
no idea. how much area does a gallon cover?

Math
start by expressing each factor in scientific notation: 1.31x10^5 3x10^-4 Now just multiply as usual.

math
the whole pipe is the sum of its parts, right?

Math
Since you have two values for y, just set them equal to each other: x^2+2x = 3x+20 x^2-x-20 = 0 (x-5)(x+4) = 0 and you're home free...

College Algebra
Once you get to 5=5 you are done. There are infinitely many solutions. If you put the two equations to the same format, they are y = 5x-5 y = 5x-5 They are the same line. Any solution to one of them is also a solution to the other.

Math
a+12d = 27 a+6d = 3(a+d) Now just solve for a and d.

Math
I agree

Maths
you need to learn to use parentheses online to make it clear what you want, since otherwise, multiplication gets done before addition. You meant (cot^2(x)(sec(x)-1))/(1+sin(x))=(sec^2(1-sin(x))/(1+sec(x)) Apply some of your elementary identities: cot^2(sec-1) = (sec-1)/tan^2...

Maths
recall that (a^3-b^3) = (a-b)(a^2+ab+b^2) sin^2+cos^2 = 1 and it all drops right out.

chemistry
for the same reason that any other endothermic reaction is so considered...

Calculus
there are lots of online graphers. You already know what the graph looks like. The critical points are where secx=0 or tanx = 0 The concavity up or down is provided by the sign of y"...

MAth
so, just plug in the numbers, and you should get 129

College Algebra
no, it is actually .05x + .10y + .25z = 7.80 Now solve 'em!

maths steve reiny bob reiny!!! Help
One side is the distance from (3,4) to 2x+y+3=0 The other side is the distance from (3,4) to x-2y-1=0 The area of the rectangle is thus |2*3+1*4+3)/?(2^2+1^2) * |1*3-2*4-1|/?(1^2+2^2) = 13

Calculus
more like dy/(1+y) = x dx ln(1+y) = x^2/2 1+y = c e^(x^2/2) y = c e^(x^2/2) - 1

Physics
ever hear of google? http://www.physicsclassroom.com/class/1DKin/Lesson-1/Distance-and-Displacement

Pre calc
so, why don't you show us how you got it? I get in QIII tan? = sin?/cos? = 5/12, so sin? = -5/13 cos? = -12/13 in QIV sin? = -1/?10 cos? = 3/?10 You don't say what you want to do with that, but sin(???) = (-5/13)(3/?10)-(-12/13)(-1/?10) = 21/(13?10)

Calculus
See your other post.

Math
a nominal rate of r compounded n times per year is (1+ r/n)^(nt) So, since you have a 4t there, .01 = r/4, making r=4% (1 + .04/4)^(4t)

Math
3.3*0.006*10 = 0.198 12*0.005*200 = 12 .198/12 = 0.0165 = 1.65x10^-2

Math
ok, so we have a circle and a tangent. A tangent to the circle will always be perpendicular to a line through the center. Now what? Ever hear of a space bar?

Math
(3.25*8)x10^(-22+3) = 26x10^-19 = 2.6x10^-18

pre calc
what are all those sin() stuff still hanging around? The final expression should just be a bunch of fractions. tan(? + ?); cos(?) = ? 1/3 ? in Quadrant III, sin(?) = 1/4 ? in Quadrant II You really need to review the signs of the trig functions in the various quadrants. In ...

pre calc
me either. why don't you show your work? I've done several already; your turn. I'm sure we can pinpoint where you go astray.

Pre calc
Funny - you and Ruth need to compare notes ... in QI sin? = 5/13 cos? = 12/13 in QII sin? = 1/?5 cos? = -2/?5 sin(?+?) = (5/13)(-2/?5)+(12/13)(1/?5) = 2/(13?5)

Pre calc
Better check my math, then. Also, maybe they don't want the radical in the denominator.

Pre calc
in QIII sin? = -5/13 cos? = -12/13 in QIV sin? = -1/?10 cos? = 3/?10 sin(? ? ?) = (-5/13)(3/?10)-(-12/13)(3/?10) = 21/(13?10)

Math - Calc
You forgot the chain rule. The result is (x^2)^(x^2) * 2x if f(x)=?[1,u] t^t dt and u = u(x) then f'(x) = f(u) * du/dx

Math
well, 141 is 11/12 std above the mean...

Calculus - Definite Integrals Please Help!
If you want h'(x), then that would be [cos(sin^3(x))+sin(x)]*cos(x)

Math - Calculus
((3x+2)/(3x-5))*3 - ((6x+2)/(6x-5))*6

statiictis
So, you want 4 of each kind. Pick any set of 4 from each kind, and then there will be 12! ways to play them. 21C4 * 13C4 * 25C4 * 12! = 2.593*10^19

Calculus
((1/2)x^2-1)^8

math
It's easier if you rewrite it as u = 1/x^4 u^2-u+1 = u^2-u+1/4 + 3/4 = (u - 1/2)^2 + 3/4 = (1/x^4 - 1/2)^2 + 3/4

Math
If all the angles are in QI, then sinA = 4/5 cosA = 3/5 sinB = 12/13 cosB = 5/13 now just use the difference formula

Science! NEED HELP URGENT
none. wavelength and velocity are related, but not amplitude. Now, if you're talking about something like a water wave, where water molecules are moving up and down, then of course, amplitude is related to the velocity of the moving particles.

Geometry
102lb * 0.45kg/lb * 2.5mg/kg = 114.75 mg

English
I think google is very helpful for these idioms. You can get various definitions and explanations.

Math
Maybe if you explain what you mean by a road a pound we can work it out. However, the perimeter of the drawing is 16 inches, and 16*5 = 80 so ...

Language Arts
ever see a cold, dreary, misty winter day? (between dawn and dusk, both the boundaries of the dark of night)

trigonomenty
Try this. http://www.cut-the-knot.org/pythagoras/cos36.shtml

math
plug in 3 for p: 3 = 14-2q

Math
distance = speed * time so just crank it out

Math
well, what numbers multiply to 40? example: 8*5 = 40 so, -8*5 = -40 8 * -5 = -40 Now, pick any other factors of 40. As long as an odd number of them are negative, the result is -40 2(-2)(-2)(-5) = -40 -10 * 4 = -40 and so on. Not as hard as it looked, was it?

math
both numbers are close to 2. What's 2+2 ?

Maths
well, he spent 1/4 + 1/3 = 7/12 so, what's left?

College Algebra
correct. Now it's smooth sailing.

Precalculus
so, you couldn't fix it and finish it off? The method was right in front of you ... r = 8sin? - 2cos? r^2 = 8r sin? - 2r cos? x^2+y^2 = 8y-2x That's ok as an equation, but I suspect you want a more standard form, so keep working it, completing the squares: x^2+2x + y^2...

Precalculus
x^2+y^2-6y-8 = 0 r^2 - 6rsin? - 8 = 0

Precalculus
I suspect a typo, but r = 8sin? - 2sin? r = 6sin? r sin? = 6sin^2? y = 6(x^2+y^2)

math
8/2 (2a+7d) = 50 50/2 (2a+49d) = 880 Solve for a and d, and then evaluate a+42d

  1. Pages:
  2. <<Prev
  3. 1
  4. 2
  5. 3
  6. 4
  7. 5
  8. 6
  9. 7
  10. 8
  11. 9
  12. 10
  13. 11
  14. 12
  15. 13
  16. 14
  17. 15
  18. Next>>

Post a New Question