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The area (in sq.units) of the region bounded by the curve y=cos⁡xy = \cos x between x=−π2,x=π2x = -\frac{\pi}{2}, x = \frac{\pi}{2} and the x-axis is

Solution

✅ Correct Option: 3

The area between the curve y=cos⁡xy = \cos x and the x-axis from x=−π2x = -\frac{\pi}{2} to x=π2x = \frac{\pi}{2} needs to be found.

The curve y=cos⁡xy = \cos x has the following values:

At x=−π2x = -\frac{\pi}{2}: cos⁡(−π2)=0\cos(-\frac{\pi}{2}) = 0

At x=0x = 0: cos⁡(0)=1\cos(0) = 1

At x=π2x = \frac{\pi}{2}: cos⁡(π2)=0\cos(\frac{\pi}{2}) = 0

Between x=−π2x = -\frac{\pi}{2} and x=π2x = \frac{\pi}{2}, the cosine curve stays above the x-axis (all values are positive).


The area bounded by the curve and the x-axis is:

Area =∫−π/2π/2cos⁡x dx= \int_{-\pi/2}^{\pi/2} \cos x \, dx


The antiderivative of cos⁡x\cos x is sin⁡x\sin x:

∫cos⁡x dx=sin⁡x+C\int \cos x \, dx = \sin x + C


Applying the limits:

Area =[sin⁡x]−π/2π/2= [\sin x]_{-\pi/2}^{\pi/2}

Area =sin⁡(π2)−sin⁡(−π2)= \sin(\frac{\pi}{2}) - \sin(-\frac{\pi}{2})

Area =1−(−1)= 1 - (-1)

Area =2= 2


Therefore, the area of the region bounded by the curve y=cos⁡xy = \cos x between x=−π2x = -\frac{\pi}{2} and x=π2x = \frac{\pi}{2} and the x-axis is 22 square units.

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