Mathematics

Help with this permutation & combination question please

There are 4 girls, 3 boys. How many ways to line them up if the boys have to be in order of increasing age. ( The boys dont have to be together)-easy way ======= just place the 4 girls in any of 7 slo

Statistics Problem regarding a Poll

a poll was conducted asking 560 if they used illegal drugs for recreation. the results were 270 answering yes, the rest answering no. if 10 people are selected at random, find the probability that 3 w

Could you solve this trigonometric problem

Using formula (1) and (2), show that sin(a-b) = sin(a)cos(b) - cos(a)-sin(b). * cos(a-b) = cos(a)cos(b) + sin(a)sin(b)..........(1) * cos(π/2 - b) = sin(b)..................................…-The issu

Can anyone differentiate this

y=e^xsinx show that d^2y/dx^2+2(dy/dx)+2y=0 thanks!! please do it in steps :)-If y = e^x sin x, then the DE should be y - 2y + 2y = 0. Use the product rule. y = e^x sin x + e^x cos x = e^x (sin x + c

What number is in the left box

http://www.designrific.com/… i think its 8 or 3 To tell you the truth it take me a while to see it but afther about 10 seconds i get it. be truthfull what do you see? This is from a 14 y/o dyspraxi

Cross product: is this a valid operation

I was wondering if its valid to use a FOIL sort of approach to this cross product (a, b, c, n are vectors) n = (a-b) x (b-c) is it true then that n = (a x b) - (a x c) - (b x b) + (b x c) so then n =

Prove the following identity: tanx+cotx=(secx)(cscx)

Thxs-tanx = sinx/cosx cotx = cosx/sinx so........... tanx + cotx = (secx)(cscx) sinx/cosx + cosx/sinx Find the LCM, which in this case is sinxcosx.......... (sin²x + cos²x) / (sinxcosx) = (secx)(

Calculus: Exponential regression on a Ti-83

Use the regression capabilities of your graphing calculator to find an exponential regression equation for the following ordered pairs:( 3, 62500 )( 5, 1562500 )( 7, 39062500 ) How would I solve thi

Can you help Combine like terms

12 g + 7g Combine like terms 6x + 3y + 5x simplify 4(x+3) -5 Can you help solve 6y + 2y = 16-are these all different problems? 1. 12g+7g=21g 2.6x+3y+5x=11x+3y 3.4(x+3)-5 =4x+12-5 =4x+7 4. 6y+2y

Integral of Cot^9(x)Csc^2(x)dx

The derivative of cot(x) is -csc^2(x) Let u = cot(x), then du = -csc^2(x)dx and -du = csc^2(x)dx So we now have ∫ -u^9 du = -((u^10) / 10) + C Substituting cot(x) back for u we get the following an

How would you do 'What number is 5.16% of 32? round the answer the the nearest hundredth if neccessary'

First, convert 5.16% to a decimal- you divide the percent by 100 - which is 0.0516. Then you multiply 32 by your decimal, 0.0516, and it comes out to1.6512. Rounding to the nearest hundredth would mak

Calculus Help! lim x -->√2 [ (1/ √2) - (1/x)]/ (√2) - x

answer = -1/2, just need to know how to do the steps. thanks in advance!!-lim x -->√2,[ (1/ √2) - (1/x)]/ (√2) - x) multiply top and bottom with -1 => lim x -->√2,- [ (1/ √2) - (1/x)]/( x - √2) ta

Find the volume V of the island z= 4 / [ 1+x^2+y^2] - 2

( the -2 is not part of the denominator.)-What is the region of integration? Assuming that the island needs z > 0, we have 4/(1 + x^2 + y^2) - 2 > 0 ==> x^2 + y^2 So, ∫∫ (4/(1+x^2+y^2) - 2) dA = ∫(

Calculus: How to express ln (.16) in terms of ln 2 and ln 5

Express ln (.16) in terms of ln 2 and ln 5.I am NOT just looking for an answer, I need to know how to do the problem.Ill be quick to award BA.Thanks in advance for any help-ln(0.16)= ln(16/100)= ln(2^

How big is a 3.5"tall x 3"wide sticker

Im planning on buying this sticker, how big would it be? http://cgi.ebay.com/ws/eBayISAPI.dll?Vie…-If you have a rule near by, its basically 3.5 inches tall by 3 inches long. Its a small sticker. Pro