Question

the positive square root of 5 root3 +4 root 3 is

Answer 1

Multiply numerator & denominator by (5√+3√)(5+3)

=(5√+3√)2(5√−3√)(5√+3√)=(5+3)2(5−3)(5+3)

=5+215−−√+35−3=5+215+35−3

=8+215−−√2=8+2152

=4+15−−√=4+15

Formulae used:

(a+b)2=a2+2ab+b2(a+b)2=a2+2ab+b2

(a−b)2=a2−b2(a−b)2=a2−b2 
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