Identify Behavior: Identify the behavior of the function as θ approaches 2π. As θ approaches 2π, sin(θ) approaches 1. This means that the term (1−sin(θ)) approaches 0. However, tan(θ) approaches infinity as θ approaches 2π from the left, and negative infinity from the right, because 2π1 and 2π2 approaches 0. The square of tan(θ), which is 2π5, will approach positive infinity from both sides since squaring a negative number results in a positive number. We have an indeterminate form of type 2π6, which means we need to manipulate the expression to resolve the indeterminate form.
Apply L'Hôpital's Rule: Apply L'Hôpital's Rule to resolve the indeterminate form.L'Hôpital's Rule states that if the limit of f(θ)/g(θ) as θ approaches a value c is of the form 0/0 or ∞/∞, then the limit of f(θ)/g(θ) as θ approaches c is the same as the limit of f′(θ)/g′(θ) as θ approaches c, provided that the derivatives exist and the limit of f′(θ)/g′(θ) is determinate.To apply L'Hôpital's Rule, we need to rewrite the expression in a form that allows us to use the rule. We can rewrite θ2 as θ3 and then as θ4. To use L'Hôpital's Rule, we need a fraction, so we can set θ5 and θ6. Now we have θ7.
Differentiate Functions: Differentiate f(θ) and g(θ) with respect to θ. The derivative of f(θ)=[sin(θ)]2∗(1−sin(θ)) is f′(θ)=2sin(θ)cos(θ)∗(1−sin(θ))−[sin(θ)]2∗cos(θ) using the product rule and chain rule. The derivative of g(θ)=cos2(θ) is g′(θ)=−2cos(θ)sin(θ) using the chain rule.
Apply L'Hôpital's Rule Correction: Apply L'Hôpital's Rule by taking the limit of f′(θ)/g′(θ) as θ approaches π/2. We now take the limit of f′(θ)/g′(θ) as θ approaches π/2. However, there is a mistake in the differentiation process in the previous step. The correct derivative of f(θ) should be f′(θ)=2sin(θ)cos(θ)⋅(1−sin(θ))−[sin(θ)]2⋅cos(θ)=2sin(θ)cos(θ)−2sin2(θ)cos(θ)−[sin(θ)]2⋅cos(θ). We need to correct this before proceeding.
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