if cos(a+ß)=0,then sin(a+ß) can be reduced to-
a. cos ß
b. cos2ß
c. sin a
d. sin2a
Answers
Answer:
(b) Cos2β
Step-by-step explanation:
I think question is like this Cos ( α - β ) = 0 then find value of Sin ( α + β )
Given---> Cos( α - β ) = 0
To find ---> Sin ( α + β ) = ?
Solution---> ATQ,
Cos ( α - β ) = 0
=> Cos ( α - β ) = Cos 90°
=> α - β = 90°
=> α = 90° + β
Now , Sin(α + β ) = Sin { ( 90° + β ) + β }
= Sin ( 90° + β + β )
= Sin ( 90° + 2β )
We know that Sin ( 90° + θ ) = Cοsθ , using it here, we get,
= Cos 2β
Additional information---->
1) Cos ( 90° +A ) = - SinA
2) tan ( 90° + A ) = - CotA
3) Cot ( 90° + A ) = - tanA
4) Sec ( 90° + A ) = - CosecA
5) Cosec ( 90° + A ) = SecA
Good Afternoon !
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i thnk ur question is like this↓↓↓↓
Question;
if cos(a+ß)=0,then sin(a-ß) can be reduced to-
a. cos ß
b. cos2ß
c. sin a
d. sin2a
Step-by-step explanation:
Given, cos(α+β)=0=cos90∘ [∴cos90∘=0]
⇒α+β=90∘
⇒α=90∘−β……………..(i)
Now, sin(α−β)=sin(90∘−β−β) [put the value from Eq.(i)]
=sin(90∘−2β)
=cos2β [∴sin(90∘−θ)=cosθ]
Hence, sin(α−β) can be reduced to cos2β.
Then Option B is Correct
if cos(a-ß)=0,then sin(a+ß) can be reduced to-