化简 (3x-4y)^2-(3x-4y)(3x+4y)

解答

化简

(3 x - 4 y)^{2} - (3 x - 4 y) (3 x + 4 y)

- 24 x y + 32 y^{2}

求解步骤

(3 x - 4 y)^{2} - (3 x - 4 y) (3 x + 4 y)

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(3 x - 4 y)^{2} : 9 x^{2} - 24 x y + 16 y^{2}

= 9 x^{2} - 24 x y + 16 y^{2} - (3 x - 4 y) (3 x + 4 y)

展开

- (3 x - 4 y) (3 x + 4 y) : - 9 x^{2} + 16 y^{2}

= 9 x^{2} - 24 x y + 16 y^{2} - 9 x^{2} + 16 y^{2}

对同类项分组

= 9 x^{2} - 9 x^{2} - 24 x y + 16 y^{2} + 16 y^{2}

∣ - 6 x ∣ = 18

x (x - 2) (x + 6) > 0

(x - 7)^{2} + x^{2} = (x + 7)^{2}

2 (x - 1) + 5 = 6 - (2 x + 2)

3 ∣ x - 3 ∣ = 18