Question

вычислить a^2-2ab+b^2-3a+3a a=10/7 b= -11/7

Answer 1

${a}^{2} - 2ab + {b}^{2} - 3a + 3b = {(a - b)}^{2} - 3(a - b) = (a - b)(a - b - 3)$
При а = 10/7, b = -11/7:
$( frac{10}{7} - ( - frac{11}{7} )( frac{10}{7} - ( - frac{11}{7} ) - 3) = ( frac{10}{7} + frac{11}{7} )( frac{10}{7} + frac{11}{7} - 3) = frac{21}{7} ( frac{21}{7} - 3) = 3 times (3 - 3) = 3 times 0 = 0$