A=5phan 13 + -5 phan 7=-20phan -41+8phan 13=-21phan41 B=-5 phan 9+8phan 15+-2phan11=4phan -9+7phan 15

A=5phan 13 + -5 phan 7=-20phan -41+8phan 13=-21phan41
B=-5 phan 9+8phan 15+-2phan11=4phan -9+7phan 15

0 bình luận về “A=5phan 13 + -5 phan 7=-20phan -41+8phan 13=-21phan41 B=-5 phan 9+8phan 15+-2phan11=4phan -9+7phan 15”

  1. Đáp án:

     $A=\frac{-5}{7}\\
    B=\frac{-2}{11}$

    Giải thích các bước giải:

    $A=\frac{5}{13}+\frac{-5}{7}+\frac{20}{-41}+\frac{8}{13}+\frac{-21}{41}\\
    =\left ( \frac{5}{13}+\frac{8}{13} \right )+\frac{-5}{7}+\left ( \frac{-20}{41}+\frac{-21}{41} \right )\\
    =\frac{13}{13}+\frac{-5}{7}+\frac{-41}{41}\\
    =1+\frac{-5}{7}-1\\
    =\frac{-5}{7}\\
    B=\frac{-5}{9}+\frac{8}{15}+\frac{-2}{11}+\frac{4}{-9}+\frac{7}{15}\\
    =\left ( \frac{-5}{9}+\frac{4}{-9}\right )+\left ( \frac{8}{15}+\frac{7}{15} \right )+\frac{-2}{11}\\
    =\frac{-9}{9}+\frac{15}{15}+\frac{-2}{11}\\
    =-1+1+\frac{-2}{11}\\
    =\frac{-2}{11}$

    Bình luận

Viết một bình luận