Tính hợp lí:
(-72).(34-12)-34.(12-72)
Bài 5: Tính hợp lí:
a. (43 − 13) ⋅ (−3) + 27 ⋅ (−14 − 16)
b. (−72) ⋅ (34 − 12) − 34 ⋅ (12 − 72)
c. (−127) ⋅ (1 − 582) − 582.127
d. −225.35 + 225.136 − 225
e. 125. (−7) ⋅ (−2) 3 ⋅ (−1) 2𝑛 (𝑛 ∈ ℕ)
f. 1 − 2 + 3 − 4 + 5 − 6 + ⋯ + 199 − 2
a, (43 - 13).(-3) + 27.(-14 - 16)
= 30.(-3) + 27.(-30)
= - 30.(3 + 27)
= -30.30
= -900
b, (-72).(34 -12) - 34.(12 - 72)
= -72.34 + 72.12 - 34.12 + 34.72
= (-72.34 + 34.72) + 12.(72 - 34)
= 12.38
= 456
c, (-127).(1 - 582) - 582.127
= - 127 + 582.127 - 582.127
= - 127
Tính: a) (43 -13).(-3) +27.(-14 - 16); b) (-72).(34 -12) -34.(12 - 72).
Tính hộ mình nha :
Tính:
a) (43 -13).(-3) +27.(-14 - 16)
b) (-72).(34 -12) -34.(12 - 72).
a) (43 -13).(-3) +27.(-14 - 16) = -900
b) (-72).(34 -12) -34.(12 - 72) = 456
b) (-72).(34 -12) -34.(12 - 72).
(-72) x (34 - 12) - 34 x (12 - 72)
= (-72) x 22 - 34 x (-60)
= (-1584) - (-2040) = 456
Tính hợp lý:
45-58+(-45)+(+58)-3
(-57)-(-12)+3-(-57)
-(-24)-(-30)+(-24)-30+8
-(-12)+(+19)-(+12)+8-19
47-(-53)+(-47)-(+53)
-(+28)+32-(-28)+(-34)
15-(+72)+(-15)+(+72)
20-(+46)+(-25)-(-46)
28-(-32)+(-28)-32+5
-75+(-49)+(+75)+49-12
Giúp e vs ạ
45-58+(-45)+(+58)-3=45-58-45+58-3=(45-45)+(58-58)-3=-3
(-57)-(-12)+3-(-57)=-57+12+3+57=(-57+57)+12+3=15
-(-24)-(-30)+(-24)-30+8=24+30-24-30+8=(24-24)+(30-30)+8=8
-(-12)+(+19)-(+12)+8-19=12+19-12+8-19=(12-12)+(19-19)+8=8
47-(-53)+(-47)-(+53)=47+53-47-53=(47-47)+(53-53)=0
-(+28)+32-(-28)+(-34)=-28+32+28-34=(-28+28)-(34-32)=-2
15-(+72)+(-15)+(+72)=15-72-15+72=(15-15)+(72-72)=0
20-(+46)+(-25)-(-46)=20-46-25+46=(20-25)+(46-46)=-5
28-(-32)+(-28)-32+5=28+32-28-32+5=(28-28)+(32-32)+5=5
-75+(-49)+(+75)+49-12=-75-49+75+49-12=(-75+75)+(49-49)-12=-12
\(...=45-58-45+58-3=-3\)
\(...=-57+12+3+57=15\)
\(...=24+30-24-30+8=8\)
\(...=12+19-12+8-19=8\)
\(...=47+53-47-53=0\)
\(...=-28+32+28-34=-2\)
\(...=15-72-15+72=0\)
\(...=20-46-25+46=-5\)
\(=...28+32-28-32+5=5\)
\(...=-75-49+75+49-12=-12\)
bài 2:
b) (-72)x(34-12)-34x(12-72)
(-72).(34 - 12) - 34 .(12 - 72)
= -72 . 34 + 72.12 - 34.12 + 34.72
= (-72.34 + 34.72) + (72 -34).12
= 0 + 38.12
= 456
a, ( -4 ). 125 . ( -25). ( -11) . (-8)
b, ( -42 ). 25 . ( -25) .( - 5) . (-4)
c, ( -72) . ( 34 - 12) - 34. ( 12 - 72)
a, (-4) . 125 . (-25) . (-11) . (-8)
= [(-4) . (-25)] . {[125 . (-8)] . (-11)}
= 100 . 11000 = 1100000
b, (-42) . 25 . (-25) . (-5) . (-4)
= [(-42) . (-5)] . [25 . (-4)] . 25
= 210 . (-100) . 25
= -5025000
Tính một cách hợp lí: 134 - 34) . (- 28) + 72 .[( -55)-45]
A. 10000.
B. 1000.
C. - 10000
D. -100000
a) 25. 69 + 31. 25 – 150;
b) 198 : [130 – (27 – 19 )2] + 20210 ;
c) 520 : (515.15 + 515.10).
d) 27– (15 – 31) – (– 2 + 21+ 5)
e) 47 – (23 + 17) – (– 17 + 47)
f) 34 – [(–12) + 34] – (49 + 12) g) 72 – (15 – 14 + 72) + 52
a: =25x100-150=2500-150=2350
c: \(=520:\left\{515\cdot25\right\}\)
=104/2575