1) (13-9)(13+9)= 4*22=88
2)(20-19)(20+19)=1*39=39
3) (11/5)2-(14/5)2= 121/25 - 196/25= -3
4)(7/2)2 - (37/10)2= 49/4 - 1369/100= - 36/25 = -1 11/25= -1,44
5)25/36 - 4/9=1/4=0,25
6) 49/81-1/36=187/324
7) 25/144-9/16=-7/18
8) 9/100-16/25= -11/20=-0,55
9)64/225-16/25=-16/45
10) 0
11) (10/3)2-(21/5)2=100/9-441/25= - 1469/225 = - 6 119/225
12) (31/6)2-(22/3)2= 951/36-484/9= - 325/12= - 27 1/12
13) (51-41)(51+41)=10*92=920
14) (54-46)(54+46)= 8*100=800
15)(76-24)(76+24)=52*100=5200
16)(328-172)(328+172)=156*500=78000
17)(11/3)2-(7/3)2=121/9-49/9=8
18) (68/9)2-(40/9)2= 4624/81-1600/81=112/3=37,3
Объяснение:
AM=AC+(1/2)CB =
AC={-2-2;5-1;6-2}={-4;4;4}
(1/2)CB= (1/2){0+2;1-5;1-6}={1;-2;-3/2}
AM=AC+(1/2)CB={-4;4;4}+{1;-2;-3/2}={-3;2;5/2}
I AM I=√[(-3)²+(2)²+(5/2)²]=√(13+25/4)=(1/2)√(52+25)
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