Question

Rezolvati : a=√144+(2+4+6+...+226) . Va rooog , am nevoie repede .
PS :totul , e sub radical

Answer 1

a=2+4+6+...+226
a=226+224+222+...+2
------------------------------------
2a=228+228+228+...+228
2a=228*113
2a=25767
a=25764:2
a=12882

a=$\sqrt{144+12882}$
a=$\sqrt{13026}$
a=114.131503

Answer 2

$a= \sqrt{144+2(1+2+3+...+113)}$

utilizam formula: $1+2+3+...+n= \frac{n(n+1)}{2}$

$a= \sqrt{144+2* \frac{113*114}{2} } = \sqrt{144+113*114} = \sqrt{144+12882}$

$a= \sqrt{13026}$