If the functions f x and g x are defined by f x -5 x -2 - g x - x -2-3 then find the value of gf 3-A- 5B-C- 11-3D- 17

The correct option is A 5Given, f(x) = 5x + 2 and g(x) = x 2/3 ∵ gf(x) = g[f(x)] ∴ nbsp;gf(3) = g[f(3)] nbsp; nbsp; nbsp; nbsp; nbsp; nbs ...

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Byju's Answer

Standard X

Mathematics

Composition of Function

If the functi...

Question

If the functions $f (x) and g (x)$ are defined by $f (x) = 5 x + 2; g (x) = \frac{x - 2}{3}$ then find the value of $g f (3) .$

\frac{11}{3}

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\frac{1}{3}

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Solution

The correct option is C 5
$Given, f (x) = 5 x + 2 and g (x) = \frac{x - 2}{3}$
$∵ g f (x) = g [f (x)]$
$∴ g f (3) = g [f (3)]$
$= g [5 (3) + 2] = g [17] = \frac{17 - 2}{3} = \frac{15}{3} = 5$

$∴ g f (3) = 5$

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If the functions f(x) and g(x) are defined by f(x)=5x+2; g(x)=x−23 then find the value of gf(3).

The correct option is C 5Given, f(x)=5x+2 and g(x)=x−23 ∵gf(x)=g[f(x)] ∴gf(3)=g[f(3)] =g[5(3)+2]=g[17]=17−23=153=5 ∴gf(3)=5

If the functions $f (x) and g (x)$ are defined by $f (x) = 5 x + 2; g (x) = \frac{x - 2}{3}$ then find the value of $g f (3) .$

The correct option is C 5
$Given, f (x) = 5 x + 2 and g (x) = \frac{x - 2}{3}$
$∵ g f (x) = g [f (x)]$
$∴ g f (3) = g [f (3)]$
$= g [5 (3) + 2] = g [17] = \frac{17 - 2}{3} = \frac{15}{3} = 5$

$∴ g f (3) = 5$