CameraIcon
CameraIcon
SearchIcon
MyQuestionIcon
MyQuestionIcon
2
You visited us 2 times! Enjoying our articles? Unlock Full Access!
Question

If tanα = mm+1 and tanβ = 12m+1, then α + β =

[IIT 1978; EAMCET 1992; Roorkee 1998; JMI EEE 2001]


A

No worries! We‘ve got your back. Try BYJU‘S free classes today!
B

Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses
C

No worries! We‘ve got your back. Try BYJU‘S free classes today!
D

None of these

No worries! We‘ve got your back. Try BYJU‘S free classes today!
Open in App
Solution

The correct option is B


We have, tan α = mm+1 and tan β = 12m+1

We know tan(α+β) = tanα+tanβ1tanαtanβ

= mm+1+12m+11m(m+1)1(2m+1) = 2m2+m+m+12m2+m+2m+1m

= 2m2+2m+12m2+2m+1 = 1 tan(α + β) = tan π4

Hence, α+β = π4.

Trick: As α+β is independent of m, therefore put m = 1,

then tanα = 12 and tanβ = 13. Therefore,

tan(α+β) = (12)+131(16) = 1. Hence α + β = π4.

(Also check for other values of m).


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