x2 + 1/x2 = 3 হলে (x6 + 1)/x3 এর মান কত?

A 3√5

B 4√5

C 2√5

D √5

Solution

Correct Answer: Option C

এখন, (x6+1)/x3
    =(x6/x3)+(1/x3)
   =x3+ 1/x3
 
দেওয়া আছে,x2+ (1/x)2=3
or,(x+1/x)2-2.x.1/x=3
or,(x+1/x)2-2=3
or,(x+1/x)2=5
or,(x+1/x)=√5

 ∴ (x3+1/x3)=(x+1/x)3-3.x.1/x.(x+1/x)
=(√5)3-3√5
=5√5-3√5
=2√5

Practice More Questions on Our App!

Download our app for free and access thousands of MCQ questions with detailed solutions