find the value of a / b + b / a , if a and b are the roots of the quadratic equation x 2 + 12 x + 3 = 0 ?
"a / b + b / a = ( a 2 + b 2 ) / ab = ( a 2 + b 2 + a + b ) / ab = [ ( a + b ) 2 - 2 ab ] / ab a + b = - 12 / 1 = - 12 ab = 3 / 1 = 3 hence a / b + b / a = [ ( - 12 ) 2 - 2 ( 3 ) ] / 3 = 126 / 3 = 42 . e )"
subtract(divide(power(negate(12), 2), 3), 2)