Recent content by sam168

suppose that (tanx)^2=tan(x-a)tan(x-b), show that tan2x=(2sinaxsinb)/(sin(a+b)) thank you in advance

Re: Geomietry yes you are right. I made a mistake. Angle BAC=90

Geomietry Triangle BAC angleABC=90 AB=AC. D and E on BC, BD=4 CE=3, F on AD and angleBFC=135, find the lenth of BF

Genius!!! Thank you very much!

cambridge y12 3u chapter10h question 27 Eight players make the quarter-finals at wimbledon, the winer of each of the quarter-finals players a semi-final to see who enters the final. a. assuming that all eight players are equally likely to win a catch, show that the probability that any tow...

my solution is different but not mach the answer assume one course in nobody choose so the first dinner have 4 choise, 2nd have 3, 3rd have 2, 4th have 1 and 5th have 4, total will be 4!. since there are 5 courses so the numbers will be 4!x5/2! why mine is wrong?

my solution is different but not mach the answer assume one course in nobody choose so the first dinner have 4 choise, 2nd have 3, 3rd have 2, 4th have 1 and 5th have 4, total will be 4!. since there are 5 courses so the numbers will be 4!x5/2! why mine is wrong?