Question

if x = 4/3 is a root (zero) of the polynomial f(x) = 6x³ - 11 x² + kx -20 , find the value of k.​

Answer 1

since f(x) zero is 4/3,

=> 6(4/3)³ - 11(4/3)² + k(4/3) - 20 = 0

=> 128/9 - 176/9 + 4k/3 - 20 = 0

=> 128 - 176 + 12k - 180 = 0

=> 12k = -228

=> k = -19

Answer 2

Step-by-step explanation:

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x=4/3

f(x)=6x³-11x²+kx-20

f(4/3)=6(4/3)³-11(4/3)²+k(4/3)-20

f(4/3)=6(64/27)-11(16/9)+4/3k-20

=2(64/9)-176/9+4/3k-20

128/9-176/9+4/3k-20=0

-48/9+4/3k-20

-48-180/9+4/3k

-228/9+4/3k

228/9=4/3k

57/3=k

is the answer of this question