If →b is the vector whose initial point divides the joining 5^i and 5^j in the ratio λ:1 and terminal point is at origin. lf |→b|≤√37, then λ∈.
A
(−∞,−6]∪[−16,∞)
Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses
B
(−∞,−3)∪[−14,∞)
No worries! We‘ve got your back. Try BYJU‘S free classes today!
C
(−∞,0)∪(12,∞)
No worries! We‘ve got your back. Try BYJU‘S free classes today!
D
[−6,−16]
No worries! We‘ve got your back. Try BYJU‘S free classes today!
Open in App
Solution
The correct option is A(−∞,−6]∪[−16,∞) Apply section formula and we get, →b=5^i+5λ^jλ+1 |→b|≤√37 ∴25×λ2+25≤(λ+12)×37 ∴25×λ2+25≤37×(λ2+2λ+1) ∴25×λ2+25≤37×λ2+74λ+37 ∴12×λ2+74λ+12≥0. ∴6×λ2+37λ+6≥0 ∴λ∈(−∞,−6]∪[−16,∞)