Solveeit Logo

Question

Question: If \(\tan \left( {\pi \cos \theta } \right)\, = \,\cot \left( {\pi \sin \theta } \right)\) then what...

If tan(πcosθ)=cot(πsinθ)\tan \left( {\pi \cos \theta } \right)\, = \,\cot \left( {\pi \sin \theta } \right) then what is the value of 19208cos2(θπ/4)19208{\cos ^2}\left( {\theta - \pi /4} \right)\,is equal to

Explanation

Solution

There are one or more trigonometric ratios to these equations, we find the value of such a function in terms of an angle, it is expressed in a simplified form. The Trigonometric Identities for Right Angled Triangles are true equations. By using as a reference, a right-angled triangle, the trigonometric functions

Formula used:
Cofunctions identities, formula
According to the trigonometric function,
tan(π2θ)=cotθ\tan \left( {\dfrac{\pi }{2} - \theta } \right) = \cot \theta
cos(π2θ)=sinθ\cos \left( {\dfrac{\pi }{2} - \theta } \right) = \sin \theta
cos(π4θ)=2n+122\cos \left( {\dfrac{\pi }{4} - \theta } \right) = \dfrac{{2n + 1}}{{2\sqrt 2 }}
Since 1<cos(π4θ)<1 - 1 < \cos \left( {\dfrac{\pi }{4} - \theta } \right) < 1
Where,
sinθ,tanθ,cosθ\sin \theta ,\tan \theta ,\cos \theta are the trigonometric identities,
θ\theta representing the angle,
π2\dfrac{\pi }{2} is an angle of 90{90^ \circ }

Complete step-by-step answer:
Given by,
tan(πcosθ)=cot(πsinθ)\tan \left( {\pi \cos \theta } \right)\, = \,\cot \left( {\pi \sin \theta } \right)
Find the value of 19208cos2(θπ/4)19208{\cos ^2}\left( {\theta - \pi /4} \right)\,
In trigonometric identities,
We know that,
tan(π2θ)=cotθ\tan \left( {\dfrac{\pi }{2} - \theta } \right) = \cot \theta
Substituting the given value, we get,
\Rightarrow θ=πcosθ\theta = \pi \cos \theta in above equation,
\Rightarrow tan(πcosθ)=tan(π2πsinθ)\tan \left( {\pi \cos \theta } \right) = \tan \left( {\dfrac{\pi }{2} - \pi \sin \theta } \right)
The range of an identities is given below,
\Rightarrow πcosθ=nπ+π2πsinθ(nI)\pi \cos \theta = n\pi + \dfrac{\pi }{2} - \pi \sin \theta \left( {n \in I} \right)
Now, we rearranging the above equation is,
Here,
\Rightarrow π(sinθ+cosθ)=(2n+1)π2\pi \left( {\sin \theta + \cos \theta } \right) = \left( {2n + 1} \right)\dfrac{\pi }{2}
Both sides the π\pi canceled,
\Rightarrow sinθ+cosθ=2n+12\sin \theta + \cos \theta = \dfrac{{2n + 1}}{2}
The trigonometric identities is
\Rightarrow cos(π2θ)=sinθ\cos \left( {\dfrac{\pi }{2} - \theta } \right) = \sin \theta
So, we can simplify the equation
\Rightarrow sinθ+cosθ=2n+12\sin \theta + \cos \theta = \dfrac{{2n + 1}}{2}
Similarly, we get,
\Rightarrow cos(π4θ)=2n+122\cos \left( {\dfrac{\pi }{4} - \theta } \right) = \dfrac{{2n + 1}}{{2\sqrt 2 }}………………..(1)\left( 1 \right)
The range between 1,1 - 1,1
Since 1<cos(π4θ)<1 - 1 < \cos \left( {\dfrac{\pi }{4} - \theta } \right) < 1
Substituting the above value in range
\Rightarrow 1<2n122<1 - 1 < \dfrac{{2n - 1}}{{2\sqrt 2 }} < 1
Substituting the value n=0,1n = 0, - 1
Where, nn is an integer
\Rightarrow cos(π4θ)=±(122)\cos \left( {\dfrac{\pi }{4} - \theta } \right) = \pm \left( {\dfrac{1}{{2\sqrt 2 }}} \right)
Rearranging the above equation
We get,
Let 22 can be written as 22\sqrt 2 \sqrt 2
So, 2×2×2cos2(π/4θ)=12 \times 2 \times 2{\cos ^2}\left( {\pi /4 - \theta } \right) = 1
On simplifying,
8cos2(π/4θ)=18{\cos ^2}\left( {\pi /4 - \theta } \right) = 1
Now we find the value of 19208cos2(θπ/4)19208{\cos ^2}\left( {\theta - \pi /4} \right)\,
Here, divide by 88in 1920819208
We get,24012401
On simplifying a given equation,
\Rightarrow 19208cos2(θπ/4)19208{\cos ^2}\left( {\theta - \pi /4} \right)\, =2401 = 2401
Hence, thus, the value of 19208cos2(θπ/4)19208{\cos ^2}\left( {\theta - \pi /4} \right)\,is equal to 24012401

Note: These equations have unknown angles for one or more trigonometric ratios. If you are not so sure about the values of different angles, the trigonometry table is a table you may refer to Sine, cosine, tangent, cotangent, cosecant, and secant trigonometric functions that describe the interaction between the triangle's sides and angles.