F.2 Maths (simplify)

您好，我是 lop，高興能解答您的問題。

(1)

5/2x - 4/3x^2
= 5(3x)/6x^2 - 4(2)/6x^2
= (15x-8)/(6x^2)

(2)

2/[(x+2)(3-x)] + 1(x-3)
= 2/[(x+2)(3-x)] + (x-3)(x+2)(3-x)/[(x+2)(3-x)]
= (-x^3+4x^2+3x-16)/[(x+2)(3-x)]

(3)

[(2x+8)/x]{[(x^4)(x-3)]/(x+4)}/(4x^2)
= (2x+8)(x^4)(x-3)/[(4x^2)(x+4)(x)]
= 2(x+4)(x^3)(x-3)/[(4x^2)(x+4)]
= (x^3)(x-3)/(2x^2)
= x(x-3)
= x^3 - 3x