Question

3x+7y³ by using formulae ​

Answer 1

Step-by-step explanation:

${(3x + 7y)}^{3} \\ {(a + b)}^{3} = {a}^{3} + {b}^{3} + 3 {a}^{2}b + 3a {b}^{2} \\ = ( {3x})^{3} + ( {7y})^{3} + 3 ({3x})^{2} (7y) + 3(3x) ({7y})^{2} \\ = 27 {x}^{3} + 343 {y}^{3} + 189 {x}^{2} y + 441x {y}^{2}$

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