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Question

Find the value of a, if one root of the equation 2x² + ax + 8 = 0 is 1.

WBBSE Class X Mathematics Quadratic Equation With One Variable 02 Mark 2022

Answer

Substitute in 2x² + ax + 8 = 0:

2(1)² + a(1) + 8 = 0

2 + a + 8 = 0

a + 10 = 0

a = −10

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