Question

$(2 \sqrt{x} + 1) {}^{3}$
expand using identities

guys I know it's a hard qiestion but I didn't find it anywhere so if you can help it would be helpful thanks​

Answer 1

Step-by-step explanation:

${(2 \sqrt{x} + 1)}^{3} \\ we \: know \: that \\ {(a + b)}^{3} = {a}^{3} + {b}^{3} + 3ab(a + b) \\ {(2 \sqrt{x} + 1) }^{3} = {(2 \sqrt{x}) }^{3} + {(1)}^{3} + 3 \: (2 \sqrt{x} )(1) \: (2 \sqrt{x} + 1) \\ = 8x \sqrt{x} + 1 + 6 \sqrt{x} (2 \sqrt{x} + 1) \\ = 8x \sqrt{x} + 1 + 12x + 6 \sqrt{x}$