What is the correct Taylor expansion for sin x around -pi/4 to the fourth term?

[pantheid]

I am asked to solve the taylor expansion of sin x around the point -pi/4 to the fourth term.

I got sin(-pi/4)+cos(-pi/4)(x+pi/4)-.5sin(-pi/4)(x+pi/4)^2-1/6(cos(-pi/4)(x+pi/4)^3 but I am getting it wrong and can't see my mistake.

 

[Ivan92]

Try evaluating for sin(-π/4), cos (-π/4),etc. It appears to be right.