x/x-5+x/x+5
3a+1/7a - 7a+b/14ab - b-1/2b
обчислити вираз

1) x/x-5+x/x+5=

X×(x+5) + x ×(x-5) /(x-5) ×(x+5) =x²+5x+x²-5x/x²+5x+x²-5x/x²-25=2x²/x²-25.

2)3a+1/ 7a - 7a+b/14ab - b-1/2b=

2b×(3a+1)-(7a+b) - 7a×(b-1)/14ab=6ab+2b-7a-b-7ab+7a/14ab=-ab+b/14ab=-a+1/14a