y=2x2-3x+1とy=x+17で
囲まれた面積は,
yを消去
2x2-3x+1=+
x2-x-=0
(x2-x-)=0
(x-)(x+)=0
x=-,
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∫ |
4 |
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面積S=- |
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(x-)(x+)dx |
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-2 |
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{-(-)}3 |
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= |
—————————————— |
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3 |
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=・ |
——— |
=・36= |
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y=-3x2+x-2とy=x2-3x-10で
囲まれた面積は,
yを消去
-3x2+x-2=x2-x-
x2-x-=0
(x2-x-2)=0
(x-)(x+)=0
x=-,
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∫ |
2 |
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面積S=- |
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(x-)(x+)dx |
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-1 |
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{-(-)}3 |
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= |
—————————————— |
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3 |
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=・ |
——— |
=・9= |
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3 |
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