Question

Calculati a=radical2 + radical 8+radical 18 +...+radical 2x99^2
Va rog frumos sa ma ajutati

Answer 1

$\it a= \sqrt2+2\sqrt2+3\sqrt2+\ ... +99\sqrt2=\sqrt{2}(1+2+3+\ ...\ +99) =\sqrt2\cdot\dfrac{99\cdot100}{2}=\\ \\ \\ =\sqrt2\cdot99\cdot50=4950\sqrt2$

Answer 2

Răspuns:

Explicație pas cu pas:

a = √2 + √8 + √18 +...+ √2x99^2

= √2 + 2√2 + 3√2 + ...+ 99√2 = √2(1 + 2 + 3 + ...+ 99)

1 + 2 + 3 + ....+ 99 = 99*(1 + 99)/2 = 99*100/2 = 4950

a = 4950√2