if a and b are the roots of the equation x 2 - 7 x + 7 = 0 , then the value of a 2 + b 2 is :
sol . ( b ) the sum of roots = a + b = 7 product of roots = ab = 8 now , a 2 + b 2 = ( a + b ) 2 - 2 ab = 49 - 14 = 35 answer a
add(power(divide(subtract(7, sqrt(subtract(power(7, const_2), multiply(const_4, 7)))), const_2), 2), power(divide(add(7, sqrt(subtract(power(7, const_2), multiply(const_4, 7)))), const_2), 2))