Solve for x: sin⁻¹(x) + sin⁻¹(√(1-x²)) = π/2 for x ∈ [0,1].

Answer: The solution for xx is x∈[0,1]x \in [0{,}1].

Step-by-step solution

Step 1: Substitute a trigonometric identity

We are given the equation sin⁡−1(x)+sin⁡−1(1−x2)=π2\sin^{-1}(x) + \sin^{-1}(\sqrt{1-x^2}) = \frac{\pi}{2}. For x∈[0,1]x \in [0{,}1], we know that 1−x2\sqrt{1-x^2} is also in [0,1][0{,}1]. A fundamental trigonometric identity states that sin⁡−1(1−x2)=cos⁡−1(x)\sin^{-1}(\sqrt{1-x^2}) = \cos^{-1}(x) when x∈[0,1]x \in [0{,}1]. This substitution simplifies the equation.

Step 2: Substitute into the original equation

Now, substitute the identity sin⁡−1(1−x2)=cos⁡−1(x)\sin^{-1}(\sqrt{1-x^2}) = \cos^{-1}(x) back into the original equation. This gives us a well-known inverse trigonometric identity.

Step 3: Apply the inverse trigonometric identity

The identity sin⁡−1(x)+cos⁡−1(x)=π2\sin^{-1}(x) + \cos^{-1}(x) = \frac{\pi}{2} holds true for all x∈[−1,1]x \in [-1, 1]. Since the problem specifies x∈[0,1]x \in [0{,}1], this identity is valid for the given domain.

Step 4: Determine the solution set

Since the identity sin⁡−1(x)+cos⁡−1(x)=π2\sin^{-1}(x) + \cos^{-1}(x) = \frac{\pi}{2} is true for all xx in the domain [0,1][0{,}1], any value of xx within this interval will satisfy the original equation. Therefore, the solution set is the entire interval [0,1][0{,}1].

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