Question

if f(x) = 5X2 - 4X + 3, find f (1) + f(2) + f(-2)
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Answer 1

Answer :

• f(1) + f(2) + f(-2) = 50.

S O L U T I O N :

Given,

• Polynomial :- f(x) = 5x² - 4x + 3

To Find,

• The value of f(1) + f(2) + f(-2).

Explanation,

Given, f(x) = 5x² - 4x + 3

[ Put f(x = 1) ]

=> f(1) = 5 × (1)² - 4 × 1 + 3

=> f(1) = 5 - 4 + 3

=> f(1) = 1 + 3

=> f(1) = 4

[ Put f(x = 2) ]

=> f(2) = 5 × (2)² - 4 × 2 + 3

=> f(2) = 5 × 4 - 8 + 3

=> f(2) = 20 - 8 + 3

=> f(2) = 12 + 3

=> f(2) = 15

[ Put f(x = -2) ]

=> f(-2) = 5 × (-2)² - 4 × -2 + 3

=> f(-2) = 5 × 4 + 8 + 3

=> f(-2) = 20 + 11

=> f(-2) = 31

Now,

f(1) + f(2) + f(-2)

=> 4 + 15 + 31

=> 19 + 31

=> 50

Therefore,

The value of f(1) + f(2) + f(-2) is 50.