作业帮数学题 运用乘法公式计算~高手来啊~
来源：学生作业帮 编辑：作业帮 分类：数学作业 时间：2024/11/05 21:58:15
数学题 运用乘法公式计算~高手来啊~
1.(三分之二X-y)(三分之二X+y)
2.(2a-3b)(3b+2a)
3.(-2b-5)(2b-5)
4.(2a+5b)^2
5.(3X-5)^2-(2X+7)^2
6.4(x+1)^2-(2x+5)(2x-5)
7.63^2
8.998*102
1.(三分之二X-y)(三分之二X+y)
2.(2a-3b)(3b+2a)
3.(-2b-5)(2b-5)
4.(2a+5b)^2
5.(3X-5)^2-(2X+7)^2
6.4(x+1)^2-(2x+5)(2x-5)
7.63^2
8.998*102
（1）原式=(2/3x)²-y²
=4/9x²-y²
(2)原式=(2a+3b)(2a-3b)
=(2a)²-(3b)²
=4a²-9b²
(3)原式=(-5+2b)(-5-2b)
=(-5)²-(2b)²
=25-4b²
(4)原式=(2a)²+2×2a×5b+(5b)²
=4a²+20ab+25b²
(5)原式=[(3x-5)+(2x+7)][(3x-5)-(2x+7)]
=(5x+2)(x-12)
=5x²-60x+2x-24
=5x²-58x-24
(6)原式=4(x²+2x+1)-(4x²-25)
=4x²+8x+4-4x²+25
=8x+29
(7)原式=(60+3)²
=60²+2×60×3+3²
=3600+360+9
=3969
(8)原式=(1000-2)(1000+2)
=1000²-2²
=1000000-4
=999996
其中第八题题目应该写错了.
=4/9x²-y²
(2)原式=(2a+3b)(2a-3b)
=(2a)²-(3b)²
=4a²-9b²
(3)原式=(-5+2b)(-5-2b)
=(-5)²-(2b)²
=25-4b²
(4)原式=(2a)²+2×2a×5b+(5b)²
=4a²+20ab+25b²
(5)原式=[(3x-5)+(2x+7)][(3x-5)-(2x+7)]
=(5x+2)(x-12)
=5x²-60x+2x-24
=5x²-58x-24
(6)原式=4(x²+2x+1)-(4x²-25)
=4x²+8x+4-4x²+25
=8x+29
(7)原式=(60+3)²
=60²+2×60×3+3²
=3600+360+9
=3969
(8)原式=(1000-2)(1000+2)
=1000²-2²
=1000000-4
=999996
其中第八题题目应该写错了.