Question

Find and simplify the following for ​f(x)=x(22-x), assuming h ≠ 0 in (C),a. f(x + h)b. f(x+h)- f(x)c. f(x+ h)- f(x)/h

Answer 1

Answer:

The answer is below

Step-by-step explanation:

Given that f(x)=x(22-x)

a) f(x)=x(22-x)

f(x + h) = (x + h)(22 - (x + h))

f(x + h) = (x + h)(22 - x - h)

f(x + h) = (22x - x² - xh + 22h - xh - h²)

f(x + h) = (-x² + 22x - h²+ 22h - 2xh)

b) f(x)=x(22-x) = 22x - x²

f(x + h) = (-x² + 22x - h²+ 22h - 2xh)

f(x+h)- f(x) = (-x² + 22x - h²+ 22h - 2xh) - (22x - x²)

f(x+h)- f(x) = -x² + 22x - h²+ 22h - 2xh - 22x + x²

f(x+h)- f(x) = -x² + x² + 22x - 22x  - h²+ 22h - 2xh

f(x+h)- f(x) = - h²+ 22h - 2xh

c) f(x+h)- f(x) = - h²+ 22h - 2xh

$\frac{f(x+h)-f(x)}{h}=\frac{- h^2+ 22h - 2xh}{h}\\ \\\frac{f(x+h)-f(x)}{h}=\frac{- h^2}{h}+\frac{22h}{h}-\frac{2xh}{h}\\\\\frac{f(x+h)-f(x)}{h}=-h+22-2x$

$\lim_{h \to 0} \frac{f(x+h)-f(x)}{h}= \lim_{h \to 0} (-h+22-2x )=22-2x$