Question

(1.) Efectuați:
dau coroniță numai ultimele 3​

Answer 1

$(x + 1) {}^{2} = {x}^{2} + 2x \times 1 + 1 {}^{2} \\ = x {}^{2} + 2x + 1 \\ \\ (1 + x) = 1 {}^{2} + 2 \times 1 \times x + x {}^{2} \\ = 1 + 2x + {x}^{2} \\ \\ (2a + 3) {}^{2} = (2a) {}^{2} + 2 \times 2a \times 3 + 3 {}^{2} \\ = 4a {}^{2} + 12a + 9 \\ \\ ( \sqrt{5} + 1) {}^{2} = ( \sqrt{5) {}^{2} } + 2 \times \sqrt{5} \times 1 + 1 {}^{2} \\ = 5 + 2 \sqrt{5} + 1 = 6 + 2 \sqrt{5} \\ \\ (0.5x {}^{2}y + y {}^{4} ) {}^{2} = (0.5 x {}^{2} y) {}^{2} + 2 \times 0.5x {}^{2} y \times y {}^{4} + (y {}^{4} ) {}^{2} \\ = 0.25x {}^{4} y {}^{2} + x {}^{2} y {}^{5} + y {}^{8}$