59+11+369=
tinh nhanh :
\(c, (-41).(59+2)+59.(41-2) d.369.(-2)-41.82\)
Tính nhanh: a) ( -41 ) x ( 59 + 2 ) + 59 x ( 41 - 2 )
b) 369 x ( -2 ) - 41 x 72
1.Tính nhanh:
a) (-134) + 51.134 + (-134).48
b) (-41) . ( 59+2 ) + 59.(41-2)
c) 369.(-2) - 41.82
d) ( 135 - 35) . (-37)+ 37.(-42 - 58)
`@` `\text {Ans}`
`\downarrow`
`a)`
`(-134) + 51.134 + (-134).48`
`= 134*(-1 + 51 - 48)`
`= 134*2`
`= 268`
`b)`
`(-41) . ( 59+2 ) + 59.(41-2)`
`= (-41)*59 - 41*2 + 59*41 + 59*2`
`= [(-41)*59 + 41*59] + (-41*2 + 59*2)`
`= 0 + 2(-41+59)`
`= 18`
`c)`
`369.(-2) - 41.82`
`= 41*9*(-2) - 41*82`
`= -41*(9*2 +82)`
`= -41*(18+82)`
`= -41*100`
`= -4100`
`d)`
`( 135 - 35) . (-37)+ 37.(-42 - 58)`
`= 100*(-37) + 37*(-100)`
`= 37*(-100 - 100)`
`= 37*(-200)`
`= -7400`
`@` `\text {Kaizuu lv uuu}`
a: =-134(1-51+48)
=-134*(-2)=268
b: =-41*59-41*2+59*41-59*2
=-41*2-59*2=-200
d: =100*(-37)+37(-100)
=100(-37-37)
=-7400
Bài 3: Tính nhanh:
a) 45. (-24) + (-10).(-12) b) (-134) + 51.134 + (-134).48
c) (-41).(59+2) + 59(41-2) d) 369.(-2) – 41. 82
a: =-45*24+120
=-1080+120
=-960
b: =134(-1+51-48)
=134*2
=268
c: =-41*59-41*2+59*41-59*2
=-2(41+59)
=-200
Tính nhanh:
a, 45.(-24) + (-10).(-12)
b, (-134) + 51.134 + (-134).48
c, (-41).(59 + 2) + 59(41 - 2)
d, 369.(-2) - 41.82
e, (135 - 35).(-37) + 37.(-42 - 58)
Các bạn trình bày các bước giải giúp mk nhé! ^^ ![]()
Bài 1: tính hợp lí
a)(-41).(59+2)+59.(41-2)
b)19.25+9.95+38.15
c)(-3879-3879-3879-3879).(-25)
d)369.(-2)-41.72
e)-54.72+54.(-28)
b)19.25+9.95+38.15 c)(-3879-3879-3879-3879).(-25)
=19.25 9.19. 5+19.2.15 = -3879.4.(-25)
= 19.( 25+9.5+2.15) = -3879.[4.(-25)]
=19.100 = -3879.(-100)
=1900 =387900
e) -54.72+54.(-28)
= -54.72-54.28
= -54.(72+28)
= -54.100
= -5400
Ta có: \(\frac{\sqrt{x}+2}{x-1}-\frac{\sqrt{x}-2}{x-2\sqrt{x}+1}\)
\(=\frac{\sqrt{x}+2}{\left(\sqrt{x}-1\right)\left(\sqrt{x}+1\right)}-\frac{\sqrt{x}-2}{\left(\sqrt{x}-1\right)^2}\)
\(=\frac{\left(\sqrt{x}+2\right)\left(\sqrt{x}-1\right)-\left(\sqrt{x}-2\right)\left(\sqrt{x}+1\right)}{\left(\sqrt{x}-1\right)^2\cdot\left(\sqrt{x}+1\right)}\)
\(=\frac{x+\sqrt{x}-2-\left(x-\sqrt{x}-2\right)}{\left(\sqrt{x}-1\right)^2\cdot\left(\sqrt{x}+1\right)}=\frac{2\sqrt{x}}{\left(\sqrt{x}-1\right)^2\cdot\left(\sqrt{x}+1\right)}\)
Ta có: \(P=\left(\frac{\sqrt{x}+2}{x-1}-\frac{\sqrt{x}-2}{x-2\sqrt{x}+1}\right):\frac{4x}{\left(x-1\right)^2}\)
\(=\frac{2\sqrt{x}}{\left(\sqrt{x}-1\right)^2\cdot\left(\sqrt{x}+1\right)}\cdot\frac{\left(x-1\right)^2}{4x}\)
\(=\frac{1}{2\sqrt{x}}\cdot\left(\sqrt{x}-1\right)^2\cdot\frac{\left(\sqrt{x}+1\right)^2}{\left(\sqrt{x}-1\right)^2\cdot\left(\sqrt{x}+1\right)}=\frac{\sqrt{x}+1}{2\sqrt{x}}\)
tính nhanh:
a) -4.2.6.25.(-7).5
b) 47.69-31.(-47)
c) 16.(38-2)-38.(16-1)
d) (-41).(59+2)+59.(41-2)
e) A=19.25+9.95+38.15
f) B= (-32).125.(-9).(-25)
g) C=(-3879-3879-3879-3879).(-25)
h) D=369.(-2)-41.72
59.(11-89)-89.(-59+11)