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Since cos x must always be positive
it just area under cosine function
so integral
 4\int\limits^\frac{ \pi }{2}_ 0  {cos (x)} \, dx=4
1 5 1
oh srrry its value is 4 only
it is ok
look at grapg of |cos(x)|
mark as best
The graph of y = |cos x| over the interval [0, 2pi] is exactly two "humps" of the cosine curve (see picture). So, we just need to integrate over one hump, then double the result: 
INT |cos x| dx (from 0 to 2pi) 
= 2 * INT cos x dx (from -pi/2 to pi/2, because this would be an interval for one hump) 
= 2 * sin x, evaluated from -pi/2 to pi/2 
= 2 * [sin(pi/2) - sin(-pi/2)] 
= 2 * [1 - (-1)] 
= 2 * 2 
= 4
1 5 1
its true only yaaar
ok cool u can mark anyone as best
hiii frnd can i ask u question please tell me that answer?