Q. Simplify to a single trig function with no denominator.csc2θ⋅cos2θAnswer:
Recall definition of cosecant function: Recall the definition of the cosecant function. The cosecant function is the reciprocal of the sine function, so csc(θ)=sin(θ)1.
Rewrite csc2θ: Rewrite csc2θ as (1/sin(θ))2. Using the definition from Step 1, we can rewrite csc2θ as (1/sin(θ))2.
Apply power to the fraction: Apply the power to the fraction.When we raise a fraction to a power, we raise both the numerator and the denominator to that power. So, (1/sin(θ))2 becomes 12/sin2θ, which simplifies to 1/sin2θ.
Multiply the expressions: Multiply the expressions.Now we multiply sin2θ1 by cos2θ. This gives us (sin2θ1)∗cos2θ.
Use Pythagorean identity: Use the Pythagorean identity for sine and cosine.The Pythagorean identity states that sin2θ+cos2θ=1. We can rearrange this to express sin2θ in terms of cos2θ: sin2θ=1−cos2θ.
Substitute sin2θ: Substitute sin2θ in the expression.Substitute sin2θ with 1−cos2θ in the expression from Step 4. This gives us 1−cos2θ1×cos2θ.
Simplify the expression: Simplify the expression.Since we have a common factor of cos2θ in the numerator and the denominator, we can simplify the expression to just cos2θ. This is because (1/(1−cos2θ))⋅cos2θ=cos2θ/(1−cos2θ)⋅(1−cos2θ)=cos2θ.