a) 60,7 + 25,5 - 38,7
b) (-9,207) + 3,8 + (-1,5030) - 2,8
c) (-12,5) + 17,55 + (-3,5) - (-2,45)
d) 2,07 + (-7,36) - (-8,97) + 1,03 - 7,64
e) (2,07 + 3,005) - (12,005 - 4,23)
f) 4,35- (2,67 - 1,65) + (3,54 - 6,33
a) 60,7 + 25,5 - 38,7=46,8
b) (-9,207) + 3,8 + (-1,5030) - 2,8=-9,71
c) (-12,5) + 17,55 + (-3,5) - (-2,45)=4
d) 2,07 + (-7,36) - (-8,97) + 1,03 - 7,6=-2,89
e) (2,07 + 3,005) - (12,005 - 4,23)=-2,7
f) 4,35- (2,67 - 1,65) + (3,54 - 6,33)=0,54
a) 60,7 + 25,5 - 38,7=46,8
b) (-9,207) + 3,8 + (-1,5030) - 2,8=-9,71
c) (-12,5) + 17,55 + (-3,5) - (-2,45)=4
d) 2,07 + (-7,36) - (-8,97) + 1,03 - 7,6=-2,89
e) (2,07 + 3,005) - (12,005 - 4,23)=-2,7
f) 4,35- (2,67 - 1,65) + (3,54 - 6,33)=0,54
Bài 2: Thực hiện phép tính (Tính hợp lí nếu có thể)
a) 60,7+25,5-38,7 b) (-9,207)+3,8+(-1,5030)-28
c) (-12,5)+17,55+(-3,5)-(-2,45) d) 2,07+(-7,36)-(-8,97)+1,03-7,64
e) (2,07+3,005)-(12,005-4,23) f) 4,35-(2,67-1,65)+(3,54-6,33)
g) (-0,4).(-0,5).(0,8) h) (-1,6).(-0,125).(-0,5) i) 3,58.24,45+3,58.75,55
giúp mình với
a: =22+25,5=47,5
b: \(=-9.207-1.503+3,8-28=-10,71-28+3,8\)
=-34,91
c: =-12,5-3,5+17,55+2,45
=20-16=4
d: =2,07+1,03-7,36-7,64+8,97=3,1-15+8,97=-2,93
e: =2,07+4,23+3,005-12,005
=6,3-9=-2,7
f: \(=4,35-2,67+1,65+3,54-6,33=6-9+3,54=3,54-3=0,54\)
(2,07+3,005)-(12,005-4,23)
(2,07+3,005)-(12,005-4,23)
=>2,07+3,005-12,005+4,23
=>(2,07+4,23)-(12,005+3,005)
=>6,3-15,01=-8,71
BT1: thực hiện phép tính
60,7+25,5-38,7
(-9,207)+3,8+(-1,5030)-2,8
60,7+25,5-38,7
= 47,5
(-9,207)+3,8+(-1,5030)-2,8
= -9,71
60,7+25,5-38,7=47,5
(-9,207)+3,8+(-1,5030)-2,8=-9,71
(2,07 - 7,005) - (12,005 - 4,23)
=2,07-7,005-12,005+4,23
=6,3-19,01
=-12,71
\(\left(2,07-7,005\right)-\left(12,005-4,23\right)\\ =-4,935-7,775\\ =-4,935+\left(-7,775\right)\\ =-12,71\)
Bài 1. Thực hiện phép tính ( Tính hợp lí nếu có thể)
|
a) 60,7 + 25,5 -38,7 b) 1,3 + 5,2 . (-2) c) -3,7 + 8,1 + 6,7 d) 12,65 + (-2,35) e) (-0,4).(-0,5).(-0,8) |
f) 3,58.24,45+3,58.75,55 g) 2,07+(-7,36)-(-8,97)+1,03 -7,64 h) 4,35 –(2,67-1,65)+(3,45-6,33) i) (0,36-36): (3,8 +0,2) j) 1,456 : 0,28 + 4,5 . 0,8 |
Bài 13 : tính nhanh
a. 5012
b . 882 + 24 . 88 + 122
c. 52 . 48
Bài 14 : rút gọn biểu thức
a. P = ( 2x - 1 ) ( 4x2 + 2x + 1 ) + ( x + 1 ) ( x2 - x + 1 )
b. Q = ( x - y ) ( x2 + xy + y2 ) - ( x + y ) ( x2 - xy + y2 ) + 2y3
Bài 13:
a) \(501^2\)
\(=\left(500+1\right)^2\)
\(=500^2+2\cdot500\cdot1+1^2\)
\(=250000+1000+1\)
\(=251001\)
b) \(88^2+24\cdot88+12^2\)
\(=88^2+2\cdot12\cdot88+12^2\)
\(=\left(88+12\right)^2\)
\(=100^2\)
\(=10000\)
c) \(52\cdot48\)
\(=\left(50+2\right)\left(50-2\right)\)
\(=50^2-2^2\)
\(=2500-4\)
\(=2496\)
Bài 14:
a) \(P=\left(2x-1\right)\left(4x^2+2x+1\right)+\left(x+1\right)\left(x^2-x+1\right)\)
\(P=\left(2x\right)^3-1+x^3+1\)
\(P=8x^3+x^3\)
\(P=9x^3\)
b) \(Q=\left(x-y\right)\left(x^2+xy+y^2\right)-\left(x+y\right)\left(x^2-xy+y^2\right)+2y^3\)
\(Q=x^3-y^3-x^3-y^3+2y^3\)
\(Q=-2y^3+2y^3\)
\(Q=0\)
Bài `14`
`a. P = ( 2x - 1 ) ( 4x^2 + 2x + 1 ) + ( x + 1 ) ( x^2 -x+1)`
`=(2x)^3-1^3 + x^3+1^3`
`=8x^3-1+x^3+1`
`= 9x^3`
__
`b, Q = ( x - y ) ( x^2 + xy + y^2 ) - ( x + y ) ( x^2 - xy + y^2)+2y^3`
`=x^3-y^3 -(x^3+y^3)+2y^3`
`=x^3-y^3 -x^3-y^3+2y^3`
`= 0`
Tính:
a) 46,827 : 90;
b) (-72,39) : (-19);
c) (-882) : 3,6;
d) 10,88 : (-0,17).
a) 46,827 : 90 = 0,5203
b) (- 72,39) : (- 19) = 3,81
c) (- 882) : 3,6 = - 245
d) 10,88 : (- 0,17) = - 64
`a,46,827:90=0,5203`
`b,(-72,39):(-19)=3,81`
`c,(-882):3,6=-245`
`d,10,88:(-0,17)=-64`
a)46,827:90=0,5203
b)(−72,39):(−19)=3,81
c)(−882):3,6=−245
d)10,88:(−0,17)=−64
Đặt tính rồi tính:
a. 3,452 + 6,08 b. 75,12 - 48,269
c. 4,567 x 5,4 d. 882 : 36
a/ 9,532; b/ 26,851 ; c/ 64,6618 ; d/ 24,5
