Evaluate: i) sin48^(@)cos42^(@)+cos48^...

Evaluate:
i) `sin48^(@)cos42^(@)+cos48^(@)sin42^(@)`
ii) `cos72^(@)cos12^(@)+sin72^(@)sin12^(@)`
ii) `cos72^(@)cos12^(@)+sin72^(@)sin12^(@)`
iii) `(tan100^(@)+tan35^(@))/(1-tan100^(@)tan35^(@))`
iv) `sinAcos(A-B)-cosAsin(A-B)`

Text Solution

Verified by Experts

i) 1, ii) `1/2`, iii) `-1`, iv) sinB

Doubtnut Promotions Banner Desktop Dark

Doubtnut Promotions Banner Mobile Dark

|

Topper's Solved these Questions

TRIGNOMETRIC FUNCTIONS
NAGEEN PRAKASHAN ENGLISH|Exercise EXERCISES 3E|19 Videos
TRIGNOMETRIC FUNCTIONS
NAGEEN PRAKASHAN ENGLISH|Exercise EXERCISES 3F|26 Videos
TRIGNOMETRIC FUNCTIONS
NAGEEN PRAKASHAN ENGLISH|Exercise EXERCISES 3C|18 Videos
STRAIGHT LINES
NAGEEN PRAKASHAN ENGLISH|Exercise Exercise|207 Videos

Similar Questions

Explore conceptually related problems

Solve sinA.cos(A-B)-cosA.sin(A-B)

Evaluate cos 48^(@) cos 42^(@) - sin48^(@) sin 42^(@)

Evaluate: sin 42^(@)sin 48^(@)-cos 42^(@)cos 48^(@)

Prove that : (i) sin42^(@)cos48^(@)+sin48^(@)cos42^(@)=1 (ii) cos70^(@)cos20^(@)-sin70^(@)sin20^(@)=0

4 cos 12 ^(@) cos 48^(@) cos 72^(@) = cos 36 ^(@)

Evaluate : (i) sin^(2)30^(@)-2cos^(3)60^(@)+3tan^(4)45^(@) (ii) (cos0^(@)+sin45^(@)+sin30^(@))(sin90^(@)-cos45^(@)+cos60^(@))

Evaluate : (cos 75^(@))/ (sin 15^(@)) + (sin 12^(@))/ (cos 78^(@)) - (cos 18^(@))/ (sin 72^(@))

The value of cos12^(@)cos24^(@)cos36^(@)cos48^(@)cos72^(@)cos84^(@), is

Evaluate : (sin 35^(@) cos 55^(@) + cos 35^(@) sin 55^(@))/ (cosec^(2) 10^(@) - tan^(2) 80^(@))

( cos 17^(@) + sin 17^(@))/( cos 17^(@) - sin 17^(@)) = tan 62^(@)

NAGEEN PRAKASHAN ENGLISH-TRIGNOMETRIC FUNCTIONS-EXERCISES 3D

Evaluate: i) sin48^(@)cos42^(@)+cos48^(@)sin42^(@) ii) cos72^(@)co...
05:29
|
The value of sin 75^(@) is equal to
09:21
|
Prove that: i) sin(A+B)cos(A-B)-cos(A+B)sin(A-B)=sin2B ii) cos(45^...
04:23
|
If cosA=4/5 and cosB=12/13, then find the values of cos(A+B) and sin(A...
05:07
|
If tanA=2, secB=-5/3, where pi lt A lt (3pi)/(2), pi/2 lt B lt pi, the...
05:57
|
If cosA=-sqrt(3)/2, sinB=-5/13, where pi/2 lt A lt pi, (3pi)/(2) lt B ...
04:08
|
If tanA=m/(m-1) and tanB=1/(2m-1), find the value of tan(A-B).
02:12
|
If tanA=m/(m-1) and tan(B)=n, find the values of tan 2A and tan 2B.
03:04
|
If tanA=m+1 and tanB=m-1, prove that tan(A-B)=2/(m^(2)).
01:43
|
Prove that: (tan(pi/4+A))/(tan(pi/4-A))=((1+tanA)/(1-tanA))^(2)
02:33
|
Prove that: cos(pi/4+A)+cos(pi/4-A)=sqrt(2)cosA
01:44
|
Prove that: cos((3pi)/(4)+A)-cos((3pi)/(4)-A)=-sqrt(2)sinA
02:18
|
Prove that: sin^2(pi/8+A/2)-sin^2(pi/8-A/2)=1/sqrt(2)sinA
01:40
|
Prove that: cos^2pi/8+sin^2(3pi)/8+sin^2(5pi)/8sin^2(7pi)/8=2
02:14
|
Prove that: cos^(2)((pi)/(8)) + cos^(2)((3pi)/(8)) + cos^(2)((5pi)/(...
02:15
|
Prove that: i) tan36^(@)+tan9^(@)+tan36^(@)tan9^(@)=1
01:41
|
Prove that: (cos8^(@)-sin8^(@))/(cos8^(@)+sin8^(@))=cot53^(@)
02:27
|
If A-B=pi/4, then prove that: (1+tanA)(1-tanB)=2
02:49
|
Prove that: (cos(60^(@)-A)+sin(30^(@)-A))/(cos(30^(@)-A)-sin(60^(@)-A)...
02:19
|
i) If A+B=pi/4 prove that: (cotA-1)(cotB-1)=2
02:00
|