SOLUTION: if f(x)=3sinx + 2cos2x, the value of (Pie/2) is

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Question 77324: if f(x)=3sinx + 2cos2x, the value of (Pie/2) is
Found 2 solutions by jim_thompson5910, chitra:
Answer by jim_thompson5910(35256) (Show Source):
You can put this solution on YOUR website!
If you're trying to evaluate:
for the function
then:

Since we can reduce the first term

notice these terms cancel

Since
Which reduces to

Which finally reduces to

So

Answer by chitra(359) (Show Source):
You can put this solution on YOUR website!
The given function is:

f(x) = 3sinx + 2cos2x

To find the value of f(pi/2)

Substituting for x, we get:

f(Pi/2) = 3 Sin (pi/2) + 2 Cos(2(pi/2)) -------------(1)

We know that the value of

Sin(pi/2) = 1 and cos (pi) = -1

Hence, the equation becomes...

f(pi/2) = 3 (1) + 2 (-1)

f(pi/2) = 3 - 2

f(pi/2) = 1

Hence, the solution.