Question

Afla patratul urmatoarelor numere
a) -2√2 b) √3+√27 c) √35:√7+5

Answer 1

(-2√2)²=(-2√2)x(-2√2)=2x2x2=8
(√3+√27)²=(√3+3√3)²=(4√3)²=4√3x4√3=4x4x3=16x3=48
(√35:√7+5)²=(√5+5)²=(√5)²+2x5x√5+5²=5+25+10√5=30+10√5

Answer 2

a) -2 $\sqrt{2}$

(-2 $\sqrt{2}$)²=4·2=8

b) $\sqrt{3}$+ $\sqrt{27}$= $\sqrt{3}$+ $3\sqrt{3}$= $4\sqrt{3}$

($4\sqrt{3}$)²=16·3=48

c) $\sqrt{35}$: $\sqrt{7}$+5= $\sqrt{5}$+5

( $\sqrt{5}$+5)²= ($\sqrt{5}$)²+2· $\sqrt{5}$·5+5²=5+ $10\sqrt{5}$+25=30+ $10\sqrt{5}$