If sec theta tan theta =p, then find the value of cosec theta.?
If sec theta tan theta =p, then find the value of cosec theta.?
Problem: If sec(theta) * tan(theta) = p, find the value of cosec(theta).
Solution:
To find the value of cosec(theta), we need to manipulate the given equation involving sec(theta) and tan(theta).
Step 1: Rewrite sec(theta) and tan(theta) in terms of sine and cosine.
Recall the definitions of sec(theta) and tan(theta):
sec(theta) = 1/cos(theta)
tan(theta) = sin(theta)/cos(theta)
Substituting these definitions into the given equation, we get:
(1/cos(theta)) * (sin(theta)/cos(theta)) = p
Simplifying further, we have:
sin(theta)/cos^2(theta) = p
Step 2: Rewrite the equation using the reciprocal identities for sine and cosine.
The reciprocal identities state:
cosec(theta) = 1/sin(theta)
sec^2(theta) = 1/cos^2(theta)
Using these identities, we can rewrite the equation as:
cosec(theta) * sec^2(theta) = p
Step 3: Substitute the value of sec^2(theta) using the Pythagorean identity.
The Pythagorean identity states:
sin^2(theta) + cos^2(theta) = 1
Rearranging this equation, we have:
cos^2(theta) = 1 - sin^2(theta)
Substituting this into our equation, we get:
cosec(theta) * (1 - sin^2(theta)) = p
Step 4: Simplify the equation and solve for cosec(theta).
Expanding the equation, we get:
cosec(theta) - cosec(theta) * sin^2(theta) = p
Rearranging the terms, we have:
cosec(theta) = p / (1 - sin^2(theta))
Using the identity cos^2(theta) = 1 - sin^2(theta), we can simplify further:
cosec(theta) = p / cos^2(theta)
Step 5: Substitute the value of cos^2(theta) using the reciprocal identity.
The reciprocal identity states:
cos(theta) = 1/sec(theta)
Substituting this into our equation, we get:
cosec(theta) = p / (1/sec^2(theta))
Simplifying further, we have:
cosec(theta) = p * sec^2(theta)
Step 6: Substitute the value of sec^2(theta) using the reciprocal identity.
The reciprocal identity states:
sec(theta) = 1/cos(theta)
Substituting this into our equation, we get:
cosec(theta) = p * (1/cos^2(theta))
Simplifying further, we have:
cosec(theta) = p / cos^2(theta)
Step 7: Substitute the value of cos^2(theta) using the Pythagorean identity.
Using the Pythagorean identity, cos^2(theta) = 1 - sin^2(theta), we can rewrite the equation as:
cosec(theta) = p / (1 - sin^2(theta))
Conclusion:
The value of cosec(theta) is p / (1 - sin^2(theta)).
To make sure you are not studying endlessly, EduRev has designed Class 10 study material, with Structured Courses, Videos, & Test Series. Plus get personalized analysis, doubt solving and improvement plans to achieve a great score in Class 10.