Question

How do I find the domain of f(x)=5x^2+4. When 0<=x<=2

#54

Answer 1

Hi

if 0 ≤ x ≤ 2

`0^2\leq x^2\leq 2^2`

Multiplied by 5.....
`5×0^2 \leq 5x^2\leq 5×2^2`

add 4 .........
`5×0^2+4 \leq 5x^2+4\leq 5×2^2`+4

so ........
`4\leq 5x^2+4\leq 24`