Question

Pls answer 27th question Pls answer friends it's very urgent the best answer will be selected as brainliest

Answer 1

a=8+3√7. b=1/8+3√7 rationalise b by multiplying 8-3√7 to both numerator and denominator.
b=(8-3√7)/(8+3√7)(8-3√7)=8-3√7/64-63=8-3√7.
${a}^{2} = {(8 + 3 \sqrt{7} ) }^{2} = {8}^{2} + {(3 \sqrt{7 })^{2} } +$
$2(8)(3 \sqrt{7} )$
=>
${a}^{2} = 64 + 63 - 48 \sqrt{7}$
similarly we get
$= > {b}^{2} = 64 + 63 - 48 \sqrt{7}$
$= > {b}^{2} = 127 - 48 \sqrt{7}$
=> so a^2+b^2=127+48√7+127-
48√7 => a^2+b^2 =254 is the answer. hope it helps you...

Answer 2

Given, a and b
Let, a= x and b = 1/x
Now, (a+b)^2= x^2+ 1/x^2 + 2(x)(1/x)
= x^2+1/x^2+2...
That implies a^2 + b^2 = -2...



Hope it helps you...