Question

If f(x) = x2 – 9 then find the value of
a) f(-3)
b) f(2)​

Answer 1

${\huge{\bf{\red{\underline{Solution:}}}}}$

${\bf{\blue{\underline{Given:}}}}$

• f(x) = x²-9

${\bf{\blue{\underline{To \:Find:}}}}$

• f(-3) = ?
• f(2) = ?

${\bf{\blue{\underline{Now:}}}}$

When f(-3)

$: \implies{\sf{ f(x) = {x}^{2} - 9}}$

$: \implies{\sf{ f(-3) = {-3}^{2} - 9}}$

$: \implies{\sf{ f(-3) = 9- 9}}$

$: \implies{\sf{ f(-3) = 0}}$

__________________________________

When f(2),

$: \implies{\sf{ f(x) = {x}^{2} - 9}}$

$: \implies{\sf{ f(2) = {2}^{2} - 9}}$

$: \implies{\sf{ f(2) = 4- 9}}$

$: \implies{\sf{ f(2) = -5}}$

Hence,

• f(-3) = 0
• f(2) = -5