1.

Find the quadratic equation whose roots are 2 times the roots of `x^(2) - 12x - 13 = 0`.A. `x^(2) - 24x - 52 = 0`B. `x^(2) - 24x - 26 = 0`C. `x^(2) - 14x - 15 = 0`D. None of these

Answer» Correct Answer - A
`f(x) = x^(2) - 12x - 13 = 0`
If the roots of `g(x)` are 2 times the roots of `f(x)` , then
`g(x) = f(x/2) - 13 = 0`
`rArr (x/2)^(2) - 12(x/2) - 13 = 0`
`rArr (x^(2))/(4) - (12x)/(2) - 13 = 0`
`rArr x^(2) - 24 x - 52 = 0`.


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