2cos2 B-1= tan2A ; cosA Γ cosB=?
2cos2 B-1= tan2A ; cosA Γ cosB=?
tejas desai , 14 Years ago
Grade
Trigonometry> trigo 2...
2 AnswersShashwat Tiwari
Write tan2A as sin2A/cos2A .......
So, 2cos2B-1=sin2A/cos2A
Hence, 2cos2B x cos2A-cos2A=sin2A............
so, 2cos2B x cos2A=sin2A+cos2A...........
2(cos2Bxcos2A)=1
so your answer is +/-(1/sqrt2)...........
G Narayana Raju
2cos2B-1=sin2A/cos2A
2cos2Bcos2A-cos2A=sin2A
2cos2Bcos2A=sin2A+cos2A
2cos2Bcos2A=1 (where sin2A+cos2A=1)
cos2Acos2B=1/2.
thus, cosAxcosB=(+/-)root(1/2).
LIVE ONLINE CLASSES
Prepraring for the competition made easy just by live online class.
Full Live Access
Study Material
Live Doubts Solving
Daily Class Assignments
Other Related Questions on trigonometry
In ABC, if cot A+cot B+cot C = cosecA cosecB cosecC, then prove that ABC is right angle triangle.
In ABC, if cot A+cot B+cot C = cosecA cosecB cosecC, then prove that ABC is right angle triangle.
trigonometry
1 Answer Available
Last Activity: 3 Years ago
- Find the general solution of equation tan3β=cot2β
For all angles between -720 and +720
- Find the general solution of equation tan3β=cot2β
For all angles between -720 and +720
trigonometry
1 Answer Available
Last Activity: 4 Years ago
To prove : Cosec(45 degree - A)Cosec(45 degree + A) = 2SecA
To prove : Cosec(45 degree - A)Cosec(45 degree + A) = 2SecA
trigonometry
1 Answer Available
Last Activity: 4 Years ago
Derive a formula for the area of the triangle, given b, A, B, and C. That is, derive the formula: (b^2sinAsinC)/(2sinB)
Derive a formula for the area of the triangle, given b, A, B, and C. That is, derive the formula: (b^2sinAsinC)/(2sinB)
trigonometry
1 Answer Available
Last Activity: 4 Years ago
WHAT IS THE LIMIT WHEN X TOWARDS TO 0 OF sin6x/5x ? limπ₯β0 π ππ6π₯/5π₯
WHAT IS THE LIMIT WHEN X TOWARDS TO 0 OF sin6x/5x ? limπ₯β0 π ππ6π₯/5π₯
trigonometry
1 Answer Available
Last Activity: 4 Years ago