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Subtract 4ab from both sides of the original formula, then the original left side = a 2*b 2+a 2+b 2-4ab+1=a 2*b 2-2ab+1+a 2-2ab+b 2=(ab-1) 2+(a-b) 2, and because the original right side = 0, so ab-1=0, a-b=0, then a=b, ab=1, so a=1, b=1, or a=-1, b=-1
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It is known that the two roots of the equation x2+(2+a)x+1+a+b=0 are x1 and x2and 00,2+a<0
then a<-2, =>0 b>1
then b a+1+1 a<0 (due to a<-2).
1/a<-1-b/a
Let y=x-1
Then (y+1) +2+a)(y+1)+a+b+1=0 gives y +(4+a)y+2a+b+4=0
Due to x1<10
0<2+b a+4 a<2+b a+4(-1-b a) (1 a<-1-b a).
b/a<-2/3
2+b/a+4/a>0
b a>-2-4 a (because a<-2,-4 a>0) then b a>-2
In summary, b a (-2, -2, 3).
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After traveling for 2 hours, Jiashan Lakuan walked 6 2 = 12 kilometers to make it bright.
B walked for 1 hour, then walked 5 1 = 5 km.
The walking route of A and B forms a straight angular triangle, which is to find the hypotenuse.
then hypotenuse = root number (12 +5) = 13 km.
A: 13 kilometers away.
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13 kilometers of noisy mountains.
A departs at 8 o'clock and walks to 10 o'clock, and the distance is 6 2 = 12 kilometers.
The journey is 5 1 = 5 km at 9 o'clock in the evening.
Data for common right-angled triangles.
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Connect the AF
af=fcef+fc=ef+af.If and only if, a, f, e three points are collinear, the minimum value = ae, the vertical distance from point A to BC.
ae=3√3/2
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It should be ac=bc
Extend BC, AE at H
Be bisects abc, then abe= cbe= hbebe ae, then aeb= heb=90°be=be
abe≌△hbe(asa)
ae=eh=1 2ah, i.e. ah=2ae
acb=∠ach=90°
Then cah=90°- h
cbf=∠hbe=90°-∠h
cah=∠cbf
cah=∠cbf
ac=bcfcb=∠ach=90°
ach≌△bcf(asa)
bf=ah=2ae
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Let's make sure that you can write the words separately.
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Be bisected by ABC
So 1= 3
Again 1= 2
So 2= 3 (equal substitution).
So bc de (the inner wrong angles are equal, and the two lines are parallel).
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Solution: BE bisected ABC
BC Ping DE
Thank you for adopting.
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