Question

If f(x) = -x2 – 1, and
g(x) = x + 5, then
f(g(x)) = –x2 + [ ? ]x + [ ]

Answer 1

`\\ \tt\hookrightarrow f(x)=-x^2-1`

`\\ \tt\hookrightarrow g(x)=x+5`

Now

`\\ \tt\hookrightarrow f(g(x))`

• Put g(x) value

`\\ \tt\hookrightarrow f(x+5)`

`\\ \tt\hookrightarrow -(x+5)^2-1`

`\\ \tt\hookrightarrow -(x^2+10x+25)-1`

`\\ \tt\hookrightarrow -x^2-10x-25-1`

`\\ \tt\hookrightarrow -x^2-10x-26`

Answer 2

• - x² - 10x - 26

Explanation:

Given:

• f(x) = - x² - 1
• g(x) = x + 5

Find f(g(x)):

• f(g(x)) =
• f(x + 5) =
• - (x + 5)² - 1 =
• - x² - 10x - 25 - 1 =
• - x² - 10x - 26