利用分式因式分解进行简便运算:
一、535²-465²
=(535+465)x(535-465)
=1000x70
=70000
二、(543²-345²)分之(321²-123²)
=(543+345)x(543-345)分之(321+123)x(321-123)
=888x198分之444x198
=888分之444
=2分之1
填空:
9x²- (4y²)=(3x+2y)(3x-2y)
( 9x²)-4m²n²=(3x+2mn)(3x-2mn )
(x²+3)²-4x²=(x²+3)²-( 2x)²=( x²-2x+3)(x²+2x+3)
已知:x²-y²=12,x+y=6,则x-y=12/6=2
把下列各式分式因
-0.16+a²b²=(ab+0.4)(ab-0.4)
(a+b+c) ²-(a-b-c)²
=(a+b+c+a-b-c)(a+b+c-a+b+c)
=2a(2b+2c)
=4a(b+c)
9a²-(b-c)²=(3a+b-c)(3a-b+c)
100p²-4q²=(10p+2q)(10p-2q)
4(2x+y)²-9(x-2y)²
=[2(2x+y)+3(x-2y)][2(2x+y)-3(x-2y)]
=(4x+2y+3x-6y)(4x+2y-3x+6y)
=(7x-4y)(x+8y)