Question

if f(x)=2xcube-13xsquare+17x+12,find f(2) and f(-3)​

Answer 1

$\large\bf\blue{Right Question➠}$

$f(x) = 2 {x}^{3} - 13 {x}^{2} + 17x + 12$

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$\large\bf\green{To\: Find➠}$

$f(2) \: and \: f( - 3)$

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$\large\bf\pink{Solve\:for\: f(2):-}$

$f(x) = 2 {x}^{3} - 13 {x}^{2} + 17x + 12$

$f(2) = 2 ({2}^{3}) - (13 \times {2}^{2}) + 17(2) + 12$

$f(2) = 2 (8) - (13 \times 4) + 34 + 12$

$f(2) = 16 - 52 + 34 + 12$

$f(2) = 10$

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$\large\bf\orange{Solve\:for\: f( - 3):-}$

$f(x) = 2 {x}^{3} - 13 {x}^{2} + 17x + 12$

$f( - 3) = 2 ({ - 3}^{3}) - (13 \times { - 3}^{2}) + 17( - 3) + 12$

$f( - 3) = 2 ( - 27) - (13 \times 9) - 51+ 12$

$f( - 3) = - 54 - 117 - 51+ 12$

$f( - 3) = - 210$

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$\large\bf\purple{Answer➠}$

$f(2) = 10$

$f( - 3) = - 210$

Answer 2

Answer :

f (2) = 10

f (-3) = -210

According to the question :

1 ) f (2)

=> $2(2)^3$- $13(2)^3$+ $17(2)$+ $12$

=> $2x ( 8 ) - 13x ( 4 ) + 17x ( 2 ) + 12$

=> $16 - 52 + 34 + 12$

=> $62 - 52$

=> $10$

2 ) f (-3)

=> $2(-3)^3$- $13(-3)^2$ + $17x (-3)$ + $12$

=> $2x ( -27 ) - 13x ( 9 ) + 17x ( -3 ) + 12$

=> $-54 - 117 - 51 + 12$

=> $-222 + 12$

=> $-210$

So, It's Done !!