SOLUTION: If f(x)=2cos^2x+sin x - 1 find the value of f (pi/2) Please help? I am able to do f(x) but the other one is confusing/

Algebra ->  Trigonometry-basics -> SOLUTION: If f(x)=2cos^2x+sin x - 1 find the value of f (pi/2) Please help? I am able to do f(x) but the other one is confusing/      Log On


   

Question 863469: If f(x)=2cos^2x+sin x - 1 find the value of f (pi/2)
Please help? I am able to do f(x) but the other one is confusing/
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
What do you mean "able to do f(x)"?
Substitute pi%2F2 for x.
f%28pi%2F2%29=2cos%5E2%28pi%2F2%29%2Bsin%28pi%2F2%29-+1
f%28pi%2F2%29=2%280%29%5E2%2B1-+1
f%28pi%2F2%29=0%2B1-1
f%28pi%2F2%29=0