七年级计算题(-3a-1/2b)(3/2a-3/4b)-(3/4b)^2(3x+2y)(3x-2y)(1-x^2)(1+x^2+x^4)

来源:学生作业帮助网 编辑:作业帮 时间:2024/11/15 04:12:47

七年级计算题(-3a-1/2b)(3/2a-3/4b)-(3/4b)^2(3x+2y)(3x-2y)(1-x^2)(1+x^2+x^4)
七年级计算题(-3a-1/2b)(3/2a-3/4b)-(3/4b)^2
(3x+2y)(3x-2y)
(1-x^2)(1+x^2+x^4)

七年级计算题(-3a-1/2b)(3/2a-3/4b)-(3/4b)^2(3x+2y)(3x-2y)(1-x^2)(1+x^2+x^4)

(-3a-1/2b)(3/2a-3/4b)-(3/4b)^2

=(3a+1/2b)(3/2a-3/4b)-(3/4b)²

=9a²/2-ab/4+3ab/4-3b²/8-9b²/16

=9a²/2+(3ab/4-ab/4)-(3b²/8+9b²/16)

=9a²/2+ab/2-15b²/16





(3x+2y)(3x-2y)

=(3x)²-(2y)²

=9x²-4y²



(1-x^2)(1+x^2+x^4)

=1³-(x²)³   (立方差公式)

=1-x^6

  1. 原式=-4.5-3/4ab+9a/4b-3/16b^2

  2. 原式=9x^2-4y^2

  3. 原式=1-x^6