Q64 of 74 Page 9

If A.M. and G.M. of roots of a quadratic equation are 8 and 5 respectively, then obtain the quadratic equation.


Let the quadratic equation be

(x - α )(x - β ) = 0

or x2 - (α + β )x + α β = 0

Roots are x = α , β

Therefore = 8 and = 5

or α + β = 8, and = 5

or = 25

Required quadratic equation is

x2 – 8x + 25 = 0

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