分解因式⑴2a(4X^2-12X)^2-36a(12X-4X^2)+162a分解因式⑴2a(4X^2-12X)^2-36a(12X-4X^2)+162a⑵a(a-b+2)-6b(b+1)⑶(a+1)(a+3)(a+5)(a+7)+15
来源:学生作业帮助网 编辑:六六作业网 时间:2024/12/18 15:35:19
分解因式⑴2a(4X^2-12X)^2-36a(12X-4X^2)+162a分解因式⑴2a(4X^2-12X)^2-36a(12X-4X^2)+162a⑵a(a-b+2)-6b(b+1)⑶(a+1)(a+3)(a+5)(a+7)+15
分解因式⑴2a(4X^2-12X)^2-36a(12X-4X^2)+162a
分解因式
⑴2a(4X^2-12X)^2-36a(12X-4X^2)+162a
⑵a(a-b+2)-6b(b+1)
⑶(a+1)(a+3)(a+5)(a+7)+15
分解因式⑴2a(4X^2-12X)^2-36a(12X-4X^2)+162a分解因式⑴2a(4X^2-12X)^2-36a(12X-4X^2)+162a⑵a(a-b+2)-6b(b+1)⑶(a+1)(a+3)(a+5)(a+7)+15
⑴2a(4X^2-12X)^2-36a(12X-4X^2)+162a
=2a(4X^2-12x)^2+36a(4X^2-12x)+162a
=2a[(4X^2-12x)^2+18(4X^2-12x)+81]
=2a[(4X^2-12x+9]^2
=2a(2x-3)^4
⑵a(a-b+2)-6b(b+1)
=a²-ab+2a-6b²-6b
=a²-ab-6b²+2a-6b
=(a-3b)(a+2b)+2(a-3b)
=(a-3b)(a+2b+2)
⑶(a+1)(a+3)(a+5)(a+7)+15
=(a+1)(a+7)(a+3)(a+5)+15
=(a²+8a+7)(a²+8a+15)+15
=(a²+8a)²+22(a²+8a)+105+15
=(a²+8a)²+22(a²+8a)+120
=(a²+8a+12)(a²+8a+10)
=(x+2)(x+6)(a²+8a+10)
(1)原式=2a[(4x^2-12x)^2-18(12x-4x^2)+81]
=2a(4x^2-12x+9)^2
=2a[(2x-3)^2]^2
=2a(2x-3)^4
(2)原式=a^2-ab+2a-6b^2-6b
...
全部展开
(1)原式=2a[(4x^2-12x)^2-18(12x-4x^2)+81]
=2a(4x^2-12x+9)^2
=2a[(2x-3)^2]^2
=2a(2x-3)^4
(2)原式=a^2-ab+2a-6b^2-6b
=(a^2-ab-6b^2)+(2a-6b)
=(a-3b)(a+2b)+2(a-3b)
=(a-3b)(a+2b+2)
(3)原式=(a+1)(a+7)(a+3)(a+5)+15
=(a^2+8a+7)(a^2+8a+15)+15
设a^2+8a=A,=(A+7)(A+15)+15
=A^2+22A+105+15
=A^2+22A+120
=(A+12)(A+10)
代入后=(a^2+8a+12)(a^2+8a+10)
=(a+2)(a+6)(a^2+8a+10)
收起
=2a[(12x-4X^2)^2-18(12X-4X^2)+81]
=2a[(12x-4X^2)(12X-4X^2-18)+81]