已知a+b=3,a^2b+ab^2=-30,则a^2-ab+b^2+11
问题描述:
已知a+b=3,a^2b+ab^2=-30,则a^2-ab+b^2+11
答
a²b + ab² = -30ab(a + b) = -303ab = -30ab = -10a² - ab + b² + 11= (a + b)² - 3ab + 11= 3² - 3×(-10) + 11= 9 + 30 + 11= 50