hw9 the derivative as a function (targets l6, d1, d2; §3.2) score: 4/9 answered: 4/9 question 5 for the…

hw9 the derivative as a function (targets l6, d1, d2; §3.2) score: 4/9 answered: 4/9 question 5 for the function f(x)=3x² + 3, evaluate the following, enter your answers in simplest form: f(x + h)= f(x + h)-f(x)= (f(x + h)-f(x))/h= question help: message instructor
Answer
Explanation:
Step1: Find $f(x + h)$
Substitute $x+h$ into $f(x)$. [ \begin{align*} f(x + h)&=3(x + h)^2+3\ &=3(x^{2}+2xh+h^{2})+3\ &=3x^{2}+6xh + 3h^{2}+3 \end{align*} ]
Step2: Find $f(x + h)-f(x)$
[ \begin{align*} f(x + h)-f(x)&=(3x^{2}+6xh + 3h^{2}+3)-(3x^{2}+3)\ &=3x^{2}+6xh + 3h^{2}+3 - 3x^{2}-3\ &=6xh+3h^{2} \end{align*} ]
Step3: Find $\frac{f(x + h)-f(x)}{h}$
[ \begin{align*} \frac{f(x + h)-f(x)}{h}&=\frac{6xh + 3h^{2}}{h}\ &=\frac{h(6x + 3h)}{h}\ &=6x+3h \end{align*} ]
Answer:
$f(x + h)=3x^{2}+6xh + 3h^{2}+3$ $f(x + h)-f(x)=6xh+3h^{2}$ $\frac{f(x + h)-f(x)}{h}=6x+3h$