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(1) 1 / 2 * 1 / 3-2 / 3 * 4 / 3
=1/6-2
=-11/6
Calculation problem: what is one part of X-1 plus one part of X? This is the calculation of fraction
1/(x-1)+1/(x+1)=2x/(x^2-1)
Forget it. Let's finish it all at once,
11. Factorization: (1) (x + y) (x + y + 2XY) + (XY + 1) (XY-1)
(2)(x+y)(x+y+2xy)+(xy+1)(xy-1)
12. If A-B = 2, a-c = 1 / 2, find the value of (B-C) ^ 2-3 (B-C) + 9 / 4
13. Solve the equation: (X-2) (x + 3) + (2-x) ^ 2 - (X-2) (2x-3) = 20
14. Calculate: 1 + 2 =?
Please answer all of you
1+2=3
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