1 93 25 279 125 154 2 − = − = =5 6 10 6 30 30 30 15 12 ⎞ 8 ⎛ 9 ⎜ + 1 ⎟ ⋅ 1,32 − ⋅ 0,1625 = 2, 24 ; 13 ⎝ 22 33 ⎠ 9 12 27 24 51 17 +1 = +1 =1 =1 ; 22 33 66 66 66 22 17 39 132 39 ⋅ 6 234 1 ⋅ 1,32 = ⋅ = = = 2,34 ; 22 22 100 100 100 8 8 1625 125 1 ⋅ 0,1625 = ⋅ = = = 0,1 ; 4) 2,34 – 0,1 = 2,24. 13 13 10000 1250 10
4) 9,3 − 4 = г) 1) 2) 3)
№ 45
а) 18 · (182 – 122) = 18 · (324 – 144) 18 · 180 = 3240 ; 12 4 ⎛ 18 + 12 ⎞ = = 0,8 ; б) 12 : ⎜ ⎟ = 12 :15 = 15 5 ⎝ 2 ⎠ в) 18 + 18 : 12=18 + 1,5 = 19,5; г) 18 · 12 – 18 : 12 = 216 – 1,5 = 214,5. № 46 ⎛ 7, 2 − 6, 4 ⎞ а) 7, 2 ⋅ ⎜ ⎟ = 7, 2 ⋅ 0, 4 = 2,88 ; 2 ⎝ ⎠
(
)
б) 6, 4 : 7, 22 − 6, 42 = 6, 4 : ( 51,84 − 40,96 ) = 6, 4 :10,88 =
6, 4 = 10,88
0,1 1 100 10 = ⋅ = ; 0,17 10 17 17 13 36 5 9 36 9 283 + 45 333 в) 7,2 + 7,2 : 6,4 = 7,2 + ⋅ = 7,2 + = + = = = 8 = 8,325 ; 40 5 32 8 5 8 40 40
=
г) 7,2 · 6,4 – 7,2 : 6,4 = 46,08 – 1,125 = 44,955 . № 47 A –3 –2 –1 0 B 2 4 6 3 C 7 –3 5 –2 4 13 34 1 A2 + 2 BC + 7 1 − − 2 2 49 57 5 7 A + 3B + C ( A + B)( B + C ) ( A + B)2 B( A + B + C ) ABC ( A + 3B )CA2 A2 B 2 + 2C
12
1 5 4 3 5
3 –2 1 6 11
6 0 8 15 1 44
1 2
–1
1
–9
1 2
2
1 5
1 3
1
–3
2
–5
–6
−7
9 25
5 1 13
3
12 19
1
8 9
3
1 2
3
15 16
−1
5 7
1 3
–42 3 13