wiz-icon
MyQuestionIcon
MyQuestionIcon
1
You visited us 1 times! Enjoying our articles? Unlock Full Access!
Question

If p+q=5 and pq=6, then p3+q3=

Open in App
Solution

Using the identity (a+b)3=a3+b3+3ab(a+b), we can write
(p+q)3=p3+q3+3pq(p+q)

It is given that p+q=5 and pq=6, therefore,

(p+q)3=p3+q3+3pq(p+q)(5)3=p3+q3+(3×6)(5)125=p3+q3+(18×5)125=p3+q3+90p3+q3=12590p3+q3=35

Hence, p3+q3=35.

flag
Suggest Corrections
thumbs-up
0
Join BYJU'S Learning Program
similar_icon
Related Videos
thumbnail
lock
Algebraic Identities
MATHEMATICS
Watch in App
Join BYJU'S Learning Program
CrossIcon