7. Calculaţi: a) (2x + 3)[(x + 3)(x - 2) + (- 16x ^ 4) / ((- 4x) ^ 2)] b) (x + 2)[(32x ^ 3 - 24x ^ 2) / (- 8x ^ 2) + 5(x - 2)] (x + 3)[(15x ^ 3 - 10x ^ 2) / (- 5x ^ 2) + 4(x - 1)] d) \{2x(x - 2) - x[5x - 3(x + 1)]\} / (- x) ; e) \{4x(x + 1) - x[6x - 4(x + 2)]\} / (2x)
