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3 votes
Find the value of the polynomial 3x

3 – 4x
2+ 7x + 5, when x = 3 and also when
x = –3.

User Miwin
by
4.8k points

1 Answer

3 votes

Answer:

71

-133

Explanation:

Given the polynomial :

3x³– 4x² + 7x + 5, when x = 3 and also when

x = –3.

Put x = 3

3(3)³– 4(3)² + 7(3) + 5

3(27) - 4(9) + 21 + 5

81 - 36 + 21 + 5

= 71

Put x = - 3

3(-3)³– 4(-3)² + 7(-3) + 5

3(-27) - 4(9) - 21 + 5

-81 - 36 - 21 + 5

= - 133

User Persia
by
4.5k points