Solving Trigonometric Equations: The Value of cot θ Given sin θ cos θ √2 cos 90 - θ
Trigonometry is a fascinating branch of mathematics that deals with the relationships between the sides and angles of triangles. One of the key concepts in trigonometry is the manipulation of trigonometric identities to simplify equations and solve for unknown variables. In this article, we will explore a specific problem involving the cotangent of an angle, given the equation sin θ cos θ √2 cos 90 - θ. We will use various trigonometric identities to simplify and solve for cot θ.
Understanding the Given Equation
The given equation is: sin θ cos θ 2 cos 90 #x00B0; - θ
Using a co-function identity, we know that:
cos 90 #x00B0; - θ sin θSubstituting this identity into the given equation, we get:
sin θ cos θ 2 sin θDividing both sides by sin θ (assuming sin θ ≠ 0):
cos θ 2 - 1 sin θExpressing cot θ in Terms of the Given Identity
We know that:
cot θ cos θ sin θSubstituting the expression for cos θ from above:
cot θ 2 - 1 sin θ sin θThis simplifies to:
cot θ 2 - 1Additional Perspective
Another way to approach this problem is to let:
θ AThen, the equation becomes:
sin A cos A 90 - Aor
or
cos A square root of 2 - 1 times sin Aor
cos A sin A square root of 2 - 1or
cot A square root of 2 - 1Since θ A, we have:
cot θ square root of 2 - 1This confirms our previous result.
Conclusion
The value of cot θ, given the equation sin θ cos θ √2 cos 90 - θ, is:
square root of 2 - 1Thus, the final answer is:
cot θ 2 - 1