Question

40 Calculați:
a = /2-(1+2+3+...+50).
-
1 1 1
1
+ + +...+
1.2 2.3 3.4 50:51

Answer 1

Răspuns:

50

Explicație pas cu pas:

..............ai in poza sper ca te am ajutat ..

Answer 2

$a=\sqrt{2(1+2+3+...+50) * ( \frac{1}{1*2} + \frac{1}{2*3} + \frac{1}{3*4} + ...+ \frac{1}{50*51} ) }$

$a = \sqrt{2(50*51:2) * ( \frac{2-1}{1*2} + \frac{3-2}{2*3} + \frac{4-3}{3*4} + ...+ \frac{51-50}{50*51}) }$

$a = \sqrt{50*51(\frac{2}{1*2} - \frac{1}{1*2} + \frac{3}{2*3} - \frac{2}{2*3} + ...+ \frac{51}{50*51} - \frac{50}{50*51} ) }$

$a = \sqrt{50*51(\frac{1}{1} - \frac{1}{2} + \frac{1}{2} - \frac{1}{3} + ...+\frac{1}{50} - \frac{1}{51} ) } }$

$a = \sqrt{50*51 (\frac{1}{1} - \frac{1}{51}) }$

$a = \sqrt{50*51*\frac{50}{51} }$

$a = \sqrt{50^{2} } = 50$