Q. 34.1( 16 Votes )

# If *x* = 2 is a root of the polynomial *f* (*x*)= 2*x*^{2}-3*x*+7*a*, find the value of *a*.

Answer :

We have,

f (x) = 2x^{2} – 3x + 7a

Put x = 2

f (2) = 2 (2)^{2} – 3 (2) + 7a

= 2 * 4 – 6 + 7a

= 8 – 6 + 7a

= 2 + 7a

Given, x = 2 is a root of f (x) = 2x^{2} – 3x + 7a

f (2) = 0

Therefore, 2 + 7a = 0

7a = -2

a =

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