Use differentiation to obtain the slope for equation y = e^3x + e^-3x and calculate the gradient values for the same values of x which are -0.4 and 0.2

Question

Use differentiation to obtain the slope for equation  y = e^3x + e^-3x and calculate the gradient values for the same values of x which are -0.4 and 0.2

anonymous · Answer

$$y' = 3e ^{3x} - 3e ^{-3x}$$ 
y'(.2) = 3.819
y'(-.4) = -9.056

anonymous · Answer

I got the answer of y = 2.37 (2dp) when x = 0.2

anonymous · Answer

Use differentiation, take the derivative which is y' in my above comment and evaluate it at .2 and -.4.

anonymous · Answer

Just sat through working it out, it makes sense now. I got y = 3.82 (2dp) for when x = 0.2

anonymous · Answer

For some reason, whenever there are e in calculus it always throws me when differentiating.