展开 ((-3y+3d+2)^2)/(16)

解答

展开

\frac{( - 3 y + 3 d + 2 ) ^{2}}{16}

- \frac{9 y d}{8} + \frac{9 y ^{2}}{16} - \frac{3 y}{4} + \frac{9 d ^{2}}{16} + \frac{3 d}{4} + \frac{1}{4}

求解步骤

\frac{( - 3 y + 3 d + 2 ) ^{2}}{16}

(- 3 y + 3 d + 2)^{2} = - 18 y d + 9 y^{2} - 12 y + 9 d^{2} + 12 d + 4

= \frac{( - 18 y d + 9 y ^{2} - 12 y + 9 d ^{2} + 12 d + 4 )}{16}

去除括号:

(- a) = - a

= \frac{- 18 y d + 9 y ^{2} - 12 y + 9 d ^{2} + 12 d + 4}{16}

使用分式法则:

\frac{a \pm b}{c} = \frac{a}{c} \pm \frac{b}{c}

\frac{- 18 y d + 9 y ^{2} - 12 y + 9 d ^{2} + 12 d + 4}{16} = - \frac{18 y d}{16} + \frac{9 y ^{2}}{16} - \frac{12 y}{16} + \frac{9 d ^{2}}{16} + \frac{12 d}{16} + \frac{4}{16}

= - \frac{18 y d}{16} + \frac{9 y ^{2}}{16} - \frac{12 y}{16} + \frac{9 d ^{2}}{16} + \frac{12 d}{16} + \frac{4}{16}

\frac{18 y d}{16} = \frac{9 y d}{8}

\frac{12 y}{16} = \frac{3 y}{4}

\frac{12 d}{16} = \frac{3 d}{4}

\frac{4}{16} = \frac{1}{4}

= - \frac{9 y d}{8} + \frac{9 y ^{2}}{16} - \frac{3 y}{4} + \frac{9 d ^{2}}{16} + \frac{3 d}{4} + \frac{1}{4}

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