Question

Square root of the Surd of 5+√21

Answer 1

A surd is an irrational number.

For Examples:

√2 = 1.414215…….. can be expressed as neither a terminating nor a non-terminating decimal.

So, √2 is a surd.

But √4 = 2 not surd.

    5+√21=((5+√(21))  * (5-√21))/(5-√21)      Here multiply the numerator and denominator by (5-√21)

           =(25-21)/(5-√21)

           =4/(5-√21)