Question

How do you find the derivative of x^2+9x, a=0? the answer is 2x+9 but how do you get there?

Answer 1

Use the power rule: \[(x ^{a})'= ax ^{a-1} \]

Answer 2

i know how to do it that way because of past expieriences, but somehow we are supposed to do it using the lim as h-->0 f(a+h)-f(a)/h

Answer 3

hi son. Just plug write really messy when you write that part out and give the correct answer you found using the power rule. You never use the limit rule except at the very begining of calc 1, never again son

Answer 4

okay thanks!