SOLUTION: If f(x)= 6sinx + 4cosx What is the derivative of f(x)? What is the derivative of f(11pi/6)?

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Question 410754: If f(x)= 6sinx + 4cosx
What is the derivative of f(x)?
What is the derivative of f(11pi/6)?
Answer by richard1234(7193) About Me  (Show Source):
You can put this solution on YOUR website!
%28d%2Fdx%29%28f%28x%29%29+=+6%2Acos%28x%29+-+4%2Asin%28x%29 (applying the derivatives of sine and cosine).

The derivative of f(x) at x+=+11pi%2F6 is simply the expression for the derivative evaluated at 11pi%2F6. This becomes

6%2Acos%2811pi%2F6%29+-+4%2Asin%2811pi%2F6%29

= 6%2A%28sqrt%283%29%2F2%29+-+4%28-1%2F2%29

= 3sqrt%283%29+%2B+2