Răspuns:
Explicație pas cu pas:
1.
9x^2 - 4 = (3x - 2)(3x + 2)
9x^2 - 6x + 4 = (3x - 2)^2
(3x - 2)(3x + 2)/(3x - 2)^2 = (3x + 2)/(3x - 2)
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2.
4x^2 - 9 = (2x - 3)(2x + 3)
4x^2 + 12x + 9 = (2x + 3)^2
(2x - 3)(2x + 3)/(2x + 3)^2 = (2x - 3)/(2x + 3)