Question

Let f(x) = 10x2 f(3 + h) = 10h^2 + 60h + 90
f(3+h) - f(3) / h = 10h + 60
what is f ' (3)?

Answer 1

as h --> 0

Answer 2

well use \[\lim_{h \rightarrow 0} (10h^2 + 60h + 90 - 90)/h = \lim_{h \rightarrow 0} h(10h + 60)/h\]

\[\lim_{h \rightarrow 0} 10h + 60 = 60\]

Answer 3

oh so basically youre using the power rule?