Question

Rationalise the denominator of :
1) root 7 + root 5 / root 7 - root 5
2) root 7 + root 2 / 9 + 2 root 14

Answer 1

1)

(√7 + √5)/( √7 - √5)

= ( √7 + √5)( √7 + √5)/( √7 - √5)(√7+√5)

= (√7 + √5)²/( √7² - √5²)

= ( 7 + 5 + 2√7.√5)/( 7 -5)

= ( 12 + 2√35)/2

= 6 + √35

====×××××××××=========×××××××======
(2)

( √7 + √2)/( 9 + 2√14)

= ( √7 + √2)/( 7 + 2 + 2√7.√2)

= ( √7 + √2)/( √7² + √2² + 2√7.√2)

=( √7 + √2)/( √7 + √2)²

= 1/( √7 + √2)

= (√7 -√2)/( √7 + √2)(√7 -√2)

= (√7 - √2)/5

Answer 2

♠Answer♠

Superman : " I'm always there to help good people "

1) (√7+√5)\(√7-√5)
on rationalising ,
multiply both numerator and denominator with ( √7+√3 )

You will get ,

(√7+√5)² \2

= 6+√35

2) (√7+√2)\(9+2√14)

on rationalising ,
multiply both numerator and denominator by (√7-√2)

see , 9+√14 = (√7+√2)²
so , the equation will become :
1\(√7+√2)
on Multiplying,

(√7-√2)/5

SOUNDS SIMPLE DOESN'T IT ?

#SupermanINFINITY