Question

Tolong bantu saya jawab soal nomor 36 tentang integral

Answer 1

Integral

y=-x^2+4x+5

y=-1/3x^3+4/2x^2+5x
{1=<x<=4}

(-x-1)(x-5)=0
-x-1=0
-x=1
x=1/-1
x=-1
atau
x-5=0
x=5

L=[-1/3(4)^3+4/2(4)^2+5(4)]-[-1/3(1)^3+4/2(1)+5(1)]
=[-1/3(64)+2(16)+20]-[-1/3(1)+2+5]
=[-64/3+32+20]-[-1/3+7]
=[-64/3+52]-[-1/3+21/3]
=[-64/3+156/3]-[20/3]
=[92/3]-[20/3]
=[72/3]
=[24] satuan luas
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Pilihan C.

Demikian semoga membantu dan bermanfaat!