PDF《图形面积问题》

2 4

7 =

8 7 $[ Q

2 +q $0 ,$  Q

2 GW- q -

2 4

7 $T - q -

2 4

7 2

4 7 =

2 4

7 8

7 $ /D q =-

9 6

7 $ Y* Q 2.KL4+ -

9 6

7 $0 ,$ ????$* Q.KL4+ -

1 6

7 ,

0 ,]+ -

9 6

7 $0 ,. /??R[ M Q 2./014 y W

1 3 x + b , ? m (-

2 4

7 ,

2 4

7 ) ??D$b =

3 2

7 , T y =

1 3 x +

3 2

7 , ~ y =

0 , 

1 3 x +

3 2

7 =

0 , /D x =-

9 6

7 , T Q

2 + -

9 6

7 $0 , ????$* Q.KL4+ -

1 6

7 ,

0 ,]+ -

9 6

7 $0 ,. !3 . #$>

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y =a x

2 +b x +c ( a ?

0 )

8 y 79:*C (

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3 ) ,

8 x 79: A `Bc*$* BKL4+4 ,

0 ,$ %&

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1 . (

1 ) -%&

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o A B???? 3??¤=?.? ?§ B*¨?$??* N? B*J?$>

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o B C???? 1? C*¨?$?}n?*x??*?$rn?* ??°¨?$[M B N.EF4 S $* M¨??±4 t $?- S

8 t .ghij$?- S .???2 /R(

1 ) Q* B.KL4+4 $0 ,・%&

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.5674 x =

1 $? ?* A.KL4+ -

2 $0 ,$??* C.KL4+0 $3 ,$? A $B $C?*??%&

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/01$ 第 3题图 D

4 a -

2 b + c =

0 1

6 a +

4 b + c =

0 c { =

3 $/D a =-

3 8 b =

3 4 c ? ? ? ? ? ? ? ? ? =

3 $ T %&

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./014 y =-

3 8 x

2 +

3 4 x +

3 2 (

2 ) S * M¨??±4 t ,  A M=

3 t $B M= A B- A M= 6-

3 t $ B N= t $>

R t B O C}?D B C=

5 $ /#$)* N? N D?_: x 7$9 x 7:* D . 第 3题解图 S B N D ∽B C O , s B N B C = N D C O , Y t

5 = N D

3 $ N D=

3 5 t $ S MB N=

1 2 B M? N D=

1 2 +6-

3 t , V

3 5 t W-

9 1

0 t

2 +

9 5 t =-

9 1

0 ( t -

1 ,

2 +

9 1

0 (

0 ? t ?

2 ) $ T ? t = 1?$S s???

9 1

0 . !4 . #$%&

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1 $0 ,`D +2 $3 ,$%&

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4 E e()* E._'

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l ?k%&

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* PCP A E4_????G HB>

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1 ) Q?m?D c =

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0 4 a +

2 b + c ? ? ? ? ? ? ? =

3 , /D a =-

1 b =

2 c ? ? ? ? ? ? ? =

3 , 第 4题图 T %&

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/014 y =-x

2 +

2 x +

3 ;

(

2 ) S A (

0 ,

3 ) , D (

2 ,

3 ) , T B C= A D=

2 , S B (-

1 ,

0 ) , T C (

1 ,

0 ) , T '

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1 2 ,

3 2 ,,

S _'

l ?????? A B C Da?4EF{|c?a$ T _'

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5674 x =

1 , T E (

3 ,

0 ) , [_'

l ./014 y = k x + m , ? E*f56}?KL???D

1 2 k + m=

3 2

3 k + m { =

0 , /D k =-

3 5 m= ? ? ? ? ? ? ?

9 5 , T _'

l ./014 y =-

3 5 x +

9 5 , ??_'

l f%&

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/01?D y =-

3 5 x +

9 5 y =- x

2 +

2 x { +

3 , /D x =

3 y { =

0 ] x =-

2 5 y =

5 1 ? ? ? ? ? ? ?

2 5 , T F (-

2 5 ,

5 1

2 5 ) , /#^$? P H ?x 7$9 l :* M, ? F N ?P H , S P*dKL4 t . T P ( t , - t

2 +

2 t +

3 ) , M( t , -

3 5 t +

9 5 ) , T P M =- t

2 +

2 t + 3- (-

3 5 t +

9 5 ) =- t

2 +

1 3

5 t +

6 5 , 第 4题解图① T S P E F= S P F M+ S P E M =

1 2 P M? F N+

1 2 P M? E H =

1 2 P M? ( F N+ E H ) =

1 2 (- t

2 +

1 3

5 t +

6 5 ) ? ( 3+

2 5 ) =-

1 7

1 0 ( t -

1 3

1 0 )

2 +

2 8

9 1

0 0 V

1 7

1 0 . T ? t =

1 3

1 0 ?$P E F.EF??$????4

2 8

9 1

0 0 V

1 7

1 0 , T ???.?k?4

3 2

8 9

1 0

0 V

1 7 10=1710;

(3)Q#??u P E A ?

9 0 ?, 第 4题解图② T ??su P A E=