Apply Trigonometric Identity: We need to evaluate the integral of sin(3x+(π/2)) from 0 to π. To simplify the integral, we can use the trigonometric identity sin(a+b)=sin(a)cos(b)+cos(a)sin(b). In this case, a=3x and b=(π/2), so sin(b)=1 and cos(b)=0. This simplifies the integral to just the integral of sin(3x).
Use Substitution Method: Now we can write the integral as: ∫0πsin(3x)dxTo integrate sin(3x), we use the substitution u=3x, which implies du=3dx or dx=3du.
Change Limits of Integration: Substituting u and dx into the integral, we get:∫03πsin(u)(3du)The limits of integration have also changed because when x=0, u=0, and when x=π, u=3π.
Evaluate Integral of sin(u): The integral now becomes: (31)∫03πsin(u)du The integral of sin(u) with respect to u is −cos(u), so we have: (31)(−cos(u)) evaluated from 0 to 3π.
Final Simplification: Evaluating the antiderivative at the bounds, we get:(31)(−cos(3π))−(31)(−cos(0))We know that cos(3π)=−1 and cos(0)=1, so the expression simplifies to:(31)(1)−(31)(−1)=(31)+(31)=32.
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