SHOW LIA
(7.
then evaluate (i)
(1+sin 0) (1 - sin o)
(1+cos 0) (1 - cos 6)
Given cote
(ii)
i
(1 +sin)
cos e
8
Answers
Answer:
answr
search
What would you like to ask?
MATHS
avatar
Asked on November 22, 2019 by
Madhumehta Bin
If cotθ=
8
7
, evaluate :
(i)
(1+cosθ)(1−cosθ)
(1+sinθ)(1−sinθ)
(ii) cot
2
θ
Share
Study later
ANSWER
Given,
cotθ=
8
7
tanθ=
cotθ
1
=
7
8
We know that,
tanθ=
adjacentSide
oppositeSide
From Pythagoras theorem,
Hypotenuse
2
=OppositeSide
2
+AdjacentSide
2
Hypotenuse
2
=8
2
+7
2
Hypotenuse
2
=64+49=113
Hypotenuse=
113
sinθ=
Hypotenuse
oppositeSide
=
113
8
cosθ=
Hypotenuse
AdjacentSide
=
113
7
Solution(i):
(1+cosθ)(1−cosθ)
(1+sinθ)(1−sinθ)
We have, a
2
−b
2
=(a+b)(a−b)
Similarly,
(1−sin
2
θ)=(1+sinθ)(1−sinθ)
(1−cos
2
θ)=(1+cosθ)(1−cosθ)
Therefore,
(1+cosθ)(1−cosθ)
(1+sinθ)(1−sinθ)
=
(1−cos
2
θ)
(1−sin
2
θ)
=
(1−(
113
7
)
2
)
(1−(
113
8
)
2
)
=
(113−49)
(113−64)
=
64
49
Solution(ii):
Given,
cotθ=
8
7
cot
2
θ=(
8
7
)
2
=
64
49
Answer By
avatar
Toppr
SHARE
How satisfied are you with the answer?
This will help us to improve better
Prev Question
Next Question
Practice important Questions
R.D. Sharma Solutions for Class 10 Chapter 5
166 Qs
Related Questions to study
If cosec A + sin A = 5
5
1
, the value of cosec
2
A+sin
2
A is 25
25
m
, m is
Study later
View Answer
If cos(α+β) =
5
4
and sin(α−β) =
13
5
tan2α=?
Study later
View Answer
VIEW MORE
Revise with Concepts
Application of Trigonometric Identities
EXAMPLE
DEFINITIONS
FORMULAES
20,000+
Learning videos
8,000+
Fun stories
10,000+
Fundamental concepts
8,00,000+
Homework Questions
Learn with Videos
Trigonometric Ratios and Identities
Trigonometric Ratios and Identities
14 min
BROWSE BY
ClassesBoardsExams
MODULES
Online ClassesMock TestsAdaptive PracticeLive Doubts
Stay upto date with our Newsletter!
Stay informed, stay ahead. Be a topper
Your email address
About Us
Brand Resources
Press
Customer Stories
Jobs
Educators
Fellowship
Learning Planet
Guides
Ask
Blog
Bytes
News
Terms of Service
Privacy Policy
Contact Us
FAQs
Google Play
App Store
Get stepwise