JAMB - Mathematics (2007 - No. 13)
Determine the value of \(\int_0 ^{\frac{\pi}{2}
}(-2cos x)dx\)
}(-2cos x)dx\)
-2
-1/2
-3
-3/2
Giải thích
\(\int_0 ^{\frac{\pi}{2}}(-2cos x)dx = [-2sin x + c]_0 ^{\frac{\pi}{2}}\\
=(-2sin\frac{\pi}{2}+c+2sin0-c)\\
=-2sin90+c+2sin0-c\\
=-2(1)+2(0)\\
=-2\)
=(-2sin\frac{\pi}{2}+c+2sin0-c)\\
=-2sin90+c+2sin0-c\\
=-2(1)+2(0)\\
=-2\)