Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
Trả lời
b)(1/3+12/67+13/41)-(79/67-28/41)
=1/3+12/67+13/41-79/67+28/41
=1/3+(12/67-79/67)+(13/41+28/41)
=1/3+(-67/67)+41/41
=1/3+(-1)+1
=1/3+0
=1/3.
a) (-5) + (-248) = - (|-5| + |-248|) = - (5 + 248) = -253.
b) 17 + |-33| = 17 + 33 = 50.
c) |-37| + |15| = 37 + 15 = 52.
a) (-5) + (-258)
= -263
b) 17 + |-33|
= 17 + 33
= 50
c) |-37| + |+15|
= 37 + 15
= 52
49\(\frac{8}{23}\) - (5\(\frac{7}{32}\) + 14\(\frac{8}{23}\))
= 49\(\frac{8}{23}\) - 5\(\frac{7}{32}\) - 14\(\frac{8}{23}\)
= (49\(\frac{8}{23}\) - 14\(\frac{8}{23}\)) - 5\(\frac{7}{32}\)
= 35 - 5 - \(\frac{7}{32}\)
= 30 - \(\frac{7}{32}\)
= \(\frac{960}{32}\) - \(\frac{7}{32}\)
= 953/32
Câu b:
71\(\frac{38}{45}\) - (43\(\frac{8}{45}\) - 1\(\frac{17}{57}\))
= 71\(\frac{38}{45}\) - 43\(\frac{8}{45}\) - 1\(\frac{17}{57}\)
= 28\(\frac{30}{45}\) - 1\(\frac{17}{57}\)
= 28\(\frac23\) - 1\(\frac{17}{57}\)
= \(\frac{86}{3}\) - \(\frac{74}{57}\)
= \(\frac{1634}{57}\) - \(\frac{74}{57}\)
= \(\frac{1560}{57}\)
= \(\frac{520}{19}\)
a) \(56+\left(-29\right)+\left(-7\right)+28+13+\left(-35\right)\)
\(=27+\left(-7\right)+28+13+\left(-35\right)\)
\(=20+28+13+\left(-35\right)\)
\(=48+13+\left(-35\right)\)
\(=61+\left(-35\right)\)
\(=26\)
b) \(\left(-213\right)+186+\left(-14\right)+217+54+\left(-49\right)\)
\(=\left(-27\right)+\left(-14\right)+217+54+\left(-49\right)\)
\(=\left(-41\right)+217+54+\left(-49\right)\)
\(=176+54+\left(-49\right)\)
\(=230+\left(-49\right)\)
\(=181\)
c) \(435+\left(-43\right)+\left(-483\right)+\left(-57\right)+383+\left(-415\right)\)
\(=392+\left(-483\right)+\left(-57\right)+383+\left(-415\right)\)
\(=\left(-91\right)+\left(-57\right)+383+\left(-415\right)\)
\(=\left(-148\right)+383+\left(-415\right)\)
\(=235+\left(-415\right)\)
\(=-180\)
a)
\(\left(-8537\right)+\left(1975+8537\right)\)
\(=\left(-8537\right)+1975+8537\)
\(=1975\)
b)
\(\left(35-17\right)+\left(17+20-35\right)\)
\(=35-17+17+20-35\)
\(=20\)
c)
\(273+\left[-34+27+\left(-273\right)\right]\)
\(=273-34+27-273\)
\(=27-34\)
\(=-7\)
Sách Giáo Khoa
a) (37 - 17).(-5) + 23.(-13 - 17)
= 20.(-5) + 23.(-30)
= (-100) + (-690) = -790
b) (-57).(67 - 34) - 67.(34 - 57)
= (-57).33 - 67.(-23)
= -1881 + 1541
= -340
hoặc: (-57).(67 - 34) - 67.(34 - 57)
= (-57).67 – (-57).34 – 67.34 + 67.57
= [67.(-57) + 67.57] – [(-57).34 + 67.34]
= 67(-57 + 57) - 34(-57 + 67)
= 67.0 - 34.10
= 0 - 340
= -340
a) (37 - 17) . (-5) + 23 . (-13 - 17) = 20 . (-5) + 23 . (-30)
= -100 - 690 = -790.
b) Cách 1:
(-57) . (67 - 34) - 67 . (34 - 57)= (-57) . 67 - (-57) . 34 - 67 . 34 + 67 . 57
= 67 . (-57 + 57) - [34 . (-57) + 34 . 67] = 0 - 34 . (-57 + 67) = -34 . 10. = -340.
Cách 2:
(-57) . (67 - 34) - 67 . (34 - 57) = (-57) . 33 - 67 . (-23) = -1881 + 1541 = -340.