4/8x5/8=?
5-1+4=?
9+3-7=?
40:8x5=?
6x4:8=?
5-1+4=8
9+3-7=5
40:8x5=25
6x4:8=3
Chúc em học giỏi nha!!!
K cho chị vs nhé cao nữ minh trang
5 - 1 + 4 = 8
9 + 3 - 7 = 5
40 : 8 x 5 = 25
6 x 4 : 8 = 3
Tính:
a) 8x5 : 4x3
b) 120x7 : (-24x5)
c) \(\dfrac{3}{4}{( - x)^3}:\dfrac{1}{8}x\)
d) -3,72x4 : (-4x2)
a) 8x5 : 4x3 = (8 : 4) . (x5 : x3) = 2.x2
b) 120x7 : (-24x5) = [120 : (-24)] . (x7 : x5) = -5.x2
c) \(\dfrac{3}{4}{( - x)^3}:\dfrac{1}{8}x = \dfrac{{ - 3}}{4}{x^3}:\dfrac{1}{8}x = \left( {\dfrac{{ - 3}}{4}:\dfrac{1}{8}} \right).({x^3}:x) = - 6{x^2}\)
d) -3,72x4 : (-4x2) = [(-3,72) : (-4)] . (x4 : x2) = 0,93x2
tinh nhanh :
7/8+1/8x3/8+1/8x5/8
\(\frac{7}{8}+\frac{1}{8}\times\frac{3}{8}+\frac{1}{8}\times\frac{5}{8}=\frac{7}{8}+\frac{1}{8}\times\left(\frac{3}{8}+\frac{5}{8}\right)=\frac{7}{8}+\frac{1}{8}\times1\)
\(=\frac{7}{8}+\frac{1}{8}=1\)
=1/8 x ( 7/8 +5/8)
= ...
ban tu lam not nha
Bài làm :
Ta có :
\(\frac{7}{8}+\frac{1}{8}\times\frac{3}{8}+\frac{1}{8}\times\frac{5}{8}\)
\(=\frac{7}{8}+\frac{1}{8}\times\left(\frac{3}{8}+\frac{5}{8}\right)\)
\(=\frac{7}{8}+\frac{1}{8}\times\frac{8}{8}\)
\(=\frac{7}{8}+\frac{1}{8}\times1\)
\(=\frac{8}{8}=1\)
-5/8x5/12+-5/8x7/12+17/8
\(\frac{-5}{8}.\frac{5}{12}+\frac{-5}{8}.\frac{7}{12}+\frac{17}{8}\)
= \(\frac{-5}{8}.\left(\frac{5}{12}+\frac{7}{12}\right)+\frac{17}{8}\)
= \(\frac{-5}{8}.\frac{12}{12}+\frac{17}{8}\)
-5/8x5/12+5/8x-7/12+17/8
Cíu zới😥😥😥
`-5/8xx5/12+5/8xx(-7/12)+17/8`
`=5/8xx(-5/12)+5/8xx(-7/12)+17/8`
`=5/8xx(-5/12-7/12)+17/8`
`=5/8xx(-12)/12+17/8`
`=5/8xx(-1)+17/8`
`=-5/8+17/8`
`=12/8=3/2`
\(-\dfrac{5}{8}\cdot\dfrac{5}{12}+\dfrac{5}{8}\cdot\left(-\dfrac{7}{12}\right)+\dfrac{17}{8}\)
\(=-\dfrac{5}{8}\cdot\dfrac{5}{12}+-\dfrac{5}{8}\cdot\dfrac{7}{12}+\dfrac{17}{8}\)
\(=-\dfrac{5}{8}\left(\dfrac{5}{12}+\dfrac{7}{12}\right)+\dfrac{17}{8}\)
\(=-\dfrac{5}{8}\cdot1+\dfrac{17}{8}\)
\(=-\dfrac{5}{8}+\dfrac{17}{8}\)
\(=\dfrac{12}{8}=\dfrac{3}{2}\)
Bài 4 Cho hai đa thức: P(x) = 8x5 + 7x - 6x2 - 3x5 + 2x2 + 1
Q(x) = 4x5 + 3x - 2x2 + x5 - 2x2 + 8
a/ Thu gọn và sắp xếp hai đa thức trên theo lũy thừa giảm dần của biến ?
b/Tính P(x) + Q(x) c/ Tìm x để P(x) =Q(x) ?
a, \(P\left(x\right)=5x^5-4x^2+7x+1;Q\left(x\right)=5x^5-4x^2+3x+8\)
b, \(P\left(x\right)+Q\left(x\right)=10x^5-8x^2+10x+9\)
c, \(P\left(x\right)=Q\left(x\right)\Rightarrow7x+1=3x+8\Leftrightarrow4x=7\Leftrightarrow x=\dfrac{7}{4}\)
a/ \(P\left(x\right)=8x^5+7x-6x^2-3x^5+2x^2+1\)
\(=8x^5-3x^5-6x^2+2x^2+7x+1\)
\(=5x^5-4x^2+7x+1\)
\(Q\left(x\right)=4x^5+3x-2x^2+x^5-2x^2+8\)
\(=4x^5+x^5-2x^2-2x^2+3x+8\)
\(=5x^5-4x^2+3x+8\)
b/ \(P\left(x\right)=5x^5-4x^2+7x+1\)
+ \(Q\left(x\right)=5x^5-4x^2+3x+8\)
____________________________
\(P\left(x\right)+Q\left(x\right)=10x^5-8x^2+10x+9\)
c/ \(P\left(x\right)=Q\left(x\right)\)
\(\Rightarrow5x^5-4x^2+7x+1=5x^5-4x^2+3x+8\)
\(\Rightarrow7x+1=3x+8\)
\(\Rightarrow4x-7=0\)
\(\Rightarrow x=\dfrac{7}{4}\)
rút gọn : 30x10^8x5^4-25^6x16^2x3:75^3x20^4+3^3x5^10x32^2
Bạn nên viết đề bằng công thức toán (biểu tượng $\sum$ góc trái khung soạn thảo) để mn hiểu đề của bạn hơn nhé.
8x5:8x5-10x2-6x3=? Giúp Mình Giải Với nha hihi!
\(\frac{8}{5}x\frac{5}{3}=\frac{8x5}{5x3}=\frac{?}{?}\)
\(\frac{8}{5}\) x \(\frac{5}{3}=\frac{8x5}{5x3}=\frac{40}{15}=\frac{8}{3}\)
\(\frac{8}{5}x\frac{5}{3}=\frac{8x5}{5x3}=\frac{40}{15}=\frac{8}{3}\)