Find the value of x: sin⁡(x)=cos⁡(x)\sin(x) = \cos(x) for x in [0, π/2\pi/2].

Answer: x=π4x = \frac{\pi}{4}

Step-by-step solution

Step 1: Rewrite the equation

The given equation is sin⁡(x)=cos⁡(x)\sin(x) = \cos(x). To solve for xx, we can divide both sides by cos⁡(x)\cos(x), provided that cos⁡(x)≠0\cos(x) \neq 0. This will allow us to express the equation in terms of tan⁡(x)\tan(x).

Step 2: Divide by cos⁡(x)\cos(x)

Dividing both sides of the equation by cos⁡(x)\cos(x) gives us sin⁡(x)cos⁡(x)=1\frac{\sin(x)}{\cos(x)} = 1. We know that sin⁡(x)cos⁡(x)\frac{\sin(x)}{\cos(x)} is equal to tan⁡(x)\tan(x).

Step 3: Express in terms of tan⁡(x)\tan(x)

Substituting tan⁡(x)\tan(x) for sin⁡(x)cos⁡(x)\frac{\sin(x)}{\cos(x)}, the equation simplifies to tan⁡(x)=1\tan(x) = 1. Now we need to find the value of xx for which the tangent is 1.

Step 4: Find the value of xx

We are looking for the angle xx in the interval [0,π/2][0, \pi/2] whose tangent is 1. We know that tan⁡(π/4)=1\tan(\pi/4) = 1. Therefore, x=π/4x = \pi/4. This value lies within the given interval.

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