1) (x+3/x)-(x/x-3)+(9/x²-3x)= (x^2 + 3 - x^2 + 3x + 9) / (x(x-3))= (3x + 12) / (x(x-3))= 3(x + 4) / x(x-3)
2) (b+c/b²-bc)-(4b/b²-c²)-(b-c/b²+bc)= ((b+c) - 4b - (b-c)) / (b^2 - bc - (4b + c^2))= (c - 4b + c) / (b^2 - bc - c^2)= (2c - 4b) / (b^2 - c^2)= 2(c - 2b) / ((b + c)(b - c))
3) (1/x-2)-(6x/x³-8)+(x-2/x²+2x+4)= ((x^3-2x) - 6x + (x^3-2)) / (x^3 - 8x + 4x^2 + 8x)= (2x^2 - 8x - 8) / (x^3 + 4x^2)= 2(x^2 - 4x - 4) / (x^2(x + 4))
1) (x+3/x)-(x/x-3)+(9/x²-3x)
= (x^2 + 3 - x^2 + 3x + 9) / (x(x-3))
= (3x + 12) / (x(x-3))
= 3(x + 4) / x(x-3)
2) (b+c/b²-bc)-(4b/b²-c²)-(b-c/b²+bc)
= ((b+c) - 4b - (b-c)) / (b^2 - bc - (4b + c^2))
= (c - 4b + c) / (b^2 - bc - c^2)
= (2c - 4b) / (b^2 - c^2)
= 2(c - 2b) / ((b + c)(b - c))
3) (1/x-2)-(6x/x³-8)+(x-2/x²+2x+4)
= ((x^3-2x) - 6x + (x^3-2)) / (x^3 - 8x + 4x^2 + 8x)
= (2x^2 - 8x - 8) / (x^3 + 4x^2)
= 2(x^2 - 4x - 4) / (x^2(x + 4))