CameraIcon
CameraIcon
SearchIcon
MyQuestionIcon
MyQuestionIcon
1
You visited us 1 times! Enjoying our articles? Unlock Full Access!
Question

If a+b+c=12 and a2+b2+c2=50, then ab + bc + ca = .

A
84
No worries! We‘ve got your back. Try BYJU‘S free classes today!
B
88
No worries! We‘ve got your back. Try BYJU‘S free classes today!
C
47
Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses
D
94
No worries! We‘ve got your back. Try BYJU‘S free classes today!
Open in App
Solution

The correct option is C 47
It is given that a+b+c=12

Using identity ,
(a+b+c)2=a2+b2+c2+2 (ab+ac+bc), we have

122=a2+b2+c2+2 (ab+ac+bc)

Substituting the value of a2+b2+c2 which is 50,we get
144=50+2 (ab+ac+bc)
2 (ab+ac+bc)=14450
2 (ab+ac+bc)=94
ab+ac+bc=47

flag
Suggest Corrections
thumbs-up
12
Join BYJU'S Learning Program
similar_icon
Related Videos
thumbnail
lock
Expansion of (a+b+c)^2
MATHEMATICS
Watch in App
Join BYJU'S Learning Program
CrossIcon