展开 (b-vf-dv)^2

解答

展开

(b - v f - d v)^{2}

- 2 b v f - 2 b d v + b^{2} + v^{2} f^{2} + 2 v fd v + d v^{2}

求解步骤

(b - v f - d v)^{2}

(b - v f - d v)^{2} = (b - v f - d v) (b - v f - d v)

= (b - v f - d v) (b - v f - d v)

乘开

(b - v f - d v) (b - v f - d v) : - 2 b v f - 2 b d v + b^{2} + v^{2} f^{2} + 2 v fd v + d v^{2}

= - 2 b v f - 2 b d v + b^{2} + v^{2} f^{2} + 2 v fd v + d v^{2}

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