Question

find the cube of 5a + 3b​

Answer 1

$(5a + 3b)^{3} = a^{3} + b^{3} + 3a^{2}b + 3ab^{2}\\ = (5a)^{3} + (3b)^{3} + (3 * (5a)^{2} * 3b) + (3 * 5a * (3b)^{2})\\ = 125a^{3} + 27b^{3} + 225a^{2}b + 145ab^{2}$

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