if you use the power rule to find the derivative of (7x^2-2) Is it just 14x? what happens to the -2? or can u not use the power rule because of the -2?

Question

valpey · Answer

Yes. The derivative of a constant is zero.

campbell_st · Answer

well if you think of 

$$f(x) = -2x^0$$

then applying the derivative rule will yield

$$f'(x) = 0 \times (-2x^{-1}) = 0$$

campbell_st · Answer

it can be written this way as 

$$-2\times x^0 = -2 \times 1 = -2$$

anonymous · Answer

Remember that when you add two functions, you can add their respective derivatives.
$$\frac{d}{dx}(7x^2-2) = \frac{d}{dx}(7x^2) + \frac{d}{dx}(-2) = \frac{d}{dx}(7x^2) + 0 =  \frac{d}{dx}(7x^2) $$
Then we use the power rule:
$$\frac{d}{dx}(7x^2) = 14x $$

anonymous · Answer

would you ever subtract the two functions, rather then add? or do you always add and apply a negative value to the second function?

campbell_st · Answer

it applies to any constant

f(x) = 3x^2 + 11

you have f'(x) = 6x 

one of the 1st concepts to understand in differentiation 

for any constant

f(x) = c 

then f'(x) = 0

anonymous · Answer

thanks for your help guys! :)