Q. 3 E4.8( 9 Votes )

# Short answer type questions:

Let us write the values of a and p if 2x^{2} + px + 6 = (2x– a) (x – 2) is an identity.

Answer :

(2x– a) (x – 2) = 2x^{2} – 4x – ax + 2a

⇒ 2x^{2} –x(a + 4) + 2a

Since the above expression is identical to 2x^{2} + px + 6, therefore their coefficients can be equated.

⇒ 2a = 6

⇒ a =3

Also, p = -(a + 4) = -7

∴ The values of a and p are 3 and -7 respectively.

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