Find the total mass of the triangular region shown below. All lengths are in centimeters, and the density of the region is
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grams/cm^2.
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Integration 6
2014-02-28 5:23 am
回答 (2)
2014-02-28 6:04 am
✔ 最佳答案
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如圖太細，可把滑鼠移至圖上，按右鍵，另存圖片到電腦上(例如桌面)，再在電腦上開啓，便會放大了。
2014-02-28 5:56 am
M/2=∫(-1 -> 0) (4+x)ydx
y=4x+4
M/2=∫(-1 -> 0) (4+x)(4x+4)dx
=4∫(-1 -> 0) (x+1)(x+4)dx
=4∫(-1 -> 0) [x^2+5x+4]dx
=4 [x^3 /3 +5x^2 /2 +4x](-1 -> 0)
=0-4( -1/3 +5/2 -4)
=22/3 g
M=44/3 g
y=4x+4
M/2=∫(-1 -> 0) (4+x)(4x+4)dx
=4∫(-1 -> 0) (x+1)(x+4)dx
=4∫(-1 -> 0) [x^2+5x+4]dx
=4 [x^3 /3 +5x^2 /2 +4x](-1 -> 0)
=0-4( -1/3 +5/2 -4)
=22/3 g
M=44/3 g
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