Question

A QUESTION FROM KG'S BOOK
If,
$x = c \sqrt{b} + 4$
then,
$find \: x + \frac{1}{x}$

Answer 1

Hello here is your answer by Sujeet yaduvanshi ☝☝☝☝☝☝☝☝☝☝☝☝☝☝



GIVEN That:-)x=cb​+4 
then,
find \: x + \frac{1}{x}findx+x1​ 


Solution:+)√b + 4 

1/x = 1/(c√b + 4) 



= x + (1/x) 

= (c√b + 4) + [1/(c√b + 4)] 

= [(c√b + 4)² + 1]/(c√b + 4) 

= [bc² + 8c√b + 16 + 1]/(c√b + 4) 


= [(bc² + 8c√b + 17).(c√b - 4)] / [(c√b + 4).(c√b - 4)] 

= [bc³√b - 4bc² + 8bc² - 32c√b + 17c√b - 68] / (bc² - 16) 

= [bc³√b + 4bc² - 15c√b - 68] / (bc² - 16)