异分母分式加减法题目(1) 3/(x-2)(x-1) - 1/x-2(2) x/2-x - 4-x²/x²-4x+4(3) 2/a²-1 + 1/a+1
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异分母分式加减法题目(1) 3/(x-2)(x-1) - 1/x-2(2) x/2-x - 4-x²/x²-4x+4(3) 2/a²-1 + 1/a+1
异分母分式加减法题目
(1) 3/(x-2)(x-1) - 1/x-2
(2) x/2-x - 4-x²/x²-4x+4
(3) 2/a²-1 + 1/a+1
异分母分式加减法题目(1) 3/(x-2)(x-1) - 1/x-2(2) x/2-x - 4-x²/x²-4x+4(3) 2/a²-1 + 1/a+1
(1) 3/(X-2) (X-1) - 1/X-2 (2) x/2-x - 4-x²/x²-4x+4
=3/(X-2) (X-1) - X-1/ (X-2) (X-1) =X/2-X - (2+X)(2-X)/(X-2)(X-2)
=3-X+1/(X-2) (X-1) =X/2-X - 2+X/2-X
=4-X/(X-2) (X-1) =X-2-X/2-X
(3) 2/a²-1 + 1/a+1 =2/X-2
=2/(a+1)(a-1) + 1/a+1
=2/(a+1)(a-1) + a-1/(a+1)(a-1)
=2+a-1/(a+1)(a-1)
=3+a/a²-1
通分
(1).3/(x-2)(x-1) - 1/x-2=3/(x-2)(x-1)-(x-1)(x-2)(x-1)=(4-x)/(x-2)(x-1)
(2) x/2-x - 4-x²/x²-4x+4=-X(X-2)/(x-2)²-4-x²/(x-2)²=2X-4/
(x-2)²=2/x-2<...
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通分
(1).3/(x-2)(x-1) - 1/x-2=3/(x-2)(x-1)-(x-1)(x-2)(x-1)=(4-x)/(x-2)(x-1)
(2) x/2-x - 4-x²/x²-4x+4=-X(X-2)/(x-2)²-4-x²/(x-2)²=2X-4/
(x-2)²=2/x-2
(3) 2/a²-1 + 1/a+1= 2/a²-1 +(a-1)/a²-1 =(a+1)/a²-1=a-1
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