Question

Rationalise 4+ root 5 + 4 - root 5

Answer 1

Correct question - Rationalize $\frac{4+√5}{4-√5}$

Solution:-

$\bf\dfrac{4+√5}{4-√5}$

• Multiplying numerator and denominator by (4+√5) , we get,

=$\bf\dfrac{(4+√5)}{(4-√5)}$ x $\bf\dfrac{(4+√5)}{(4+√5)}$

=$\bf\dfrac{(4+√5)²}{(4)²-(√5)²}$

=$\bf\dfrac{(4)²+(√5)²+(2*4*√5)}{16-5}$

=$\bf\dfrac{21+8√5}{11}$

Answer 2

4+√5/4-√5

4+√5/4-√5×4+√5

(4+√5)(4+√5)/4^2-√5^2

16+4√5+4√5+5/16-5

21+8√5/11