7/2x3/4+17/8x2/3+3/4x1/2+7/8x3/3
tính giá trị biểu thức
1/2x3/4:6/5 2/3+1/6:7/12 8x3/5:12/5 4/9+3/4-1/3
a: \(=\dfrac{1}{2}\cdot\dfrac{3}{4}\cdot\dfrac{5}{6}=\dfrac{15}{48}=\dfrac{5}{16}\)
b: \(=\dfrac{2}{3}+\dfrac{12}{42}=\dfrac{2}{3}+\dfrac{2}{7}=\dfrac{20}{21}\)
c: \(=\dfrac{24}{5}\cdot\dfrac{5}{12}=2\)
d: \(=\dfrac{1}{9}+\dfrac{3}{4}=\dfrac{4+27}{36}=\dfrac{31}{36}\)
tính giá trị biểu thức
1/2x3/4:6/5 2/3+1/6:7/12 8x3/5:12/5 4/9+3/4-1/3
\(\dfrac{1}{2}\times\dfrac{3}{4}:\dfrac{6}{5}=\dfrac{3}{8}:\dfrac{6}{5}=\dfrac{5}{16}\)
\(\dfrac{2}{3}+\dfrac{1}{6}:\dfrac{7}{12}=\dfrac{2}{3}+\dfrac{2}{7}=\dfrac{14}{21}+\dfrac{6}{21}=\dfrac{20}{21}\)
\(8\times\dfrac{3}{5}:\dfrac{12}{5}=\dfrac{24}{5}:\dfrac{12}{5}=2\)
\(\dfrac{4}{9}+\dfrac{3}{4}-\dfrac{1}{3}=\dfrac{16}{36}+\dfrac{27}{36}-\dfrac{12}{36}=\dfrac{31}{36}\)
Phân tích
a,(x2 + x + 2)3 - (x+1)3 = x6 +1 b,(x2 + 10x + 8)2 - (8x + 4)(x2 + 8x+7)
c, A= x4 + 2x3 + 3x2 + 2x+4 d,B= x4 + 4x3 + +8x2 + 8x + 4
e, C= x4 - 2x3 + 5x2 - 4x + 4
tính giá trị biểu thức
1/2x3/4:6/5 2/3+1/6:7/12 8x3/5:12/5 4/9+3/4-1/3
2 bn lm xong trước mk tick
1: \(=\dfrac{3}{8}\cdot\dfrac{5}{6}=\dfrac{15}{24}=\dfrac{5}{8}\)
2: \(=\dfrac{2}{3}+\dfrac{12}{42}=\dfrac{2}{3}+\dfrac{2}{7}=\dfrac{14+6}{21}=\dfrac{20}{21}\)
3: \(=\dfrac{24}{5}\cdot\dfrac{5}{12}=2\)
4: \(=\dfrac{1}{3}+\dfrac{3}{4}=\dfrac{4+9}{12}=\dfrac{13}{12}\)
`1/2xx3/4:6/5= 1/2 xx 3/4 xx 5/6 = 3/8 xx 5/6 =5/16`
`2/3+1/6:7/12 = 2/3 + 1/6 xx 12/7 = 2/3 + 2/7 = 14/21 + 6/21 = 20/21`
`8xx3/5:12/5= 8xx 3/5 xx 5/12 = 24/5 xx 5/12 = 2`
`4/9+3/4-1/3= (16/36 + 27/36 ) - 1/3 = 43/36 - 1/3 = 31/36`
`1/2xx3/4:6/5`
`=1/2xx3/4xx5/6`
`=3/8xx5/6`
`=15/48`
`=5/16`
__
`2/3+1/6:7/12`
`=2/3+1/6xx12/7`
`=2/3+2/7`
`=14/21+6/21`
`=20/21`
__
`8xx3/5:12/5`
`=8xx3/5xx5/12`
`=8xx1/4`
`=8/4`
`=2`
__
`4/9+3/4-1/3`
`=(4/9-1/3)+3/4`
`=(4/9-3/9)+3/4`
`=1/9+3/4`
`=4/36+27/36`
`=31/36`
Gỉai các phương trình sau;
a, 3x2 - 8x2 - 2x + 3 = 0
b, x3 - 4x2 + 7x - 6 = 0
c, 2x3 + 7x2 + 7x + 2 = 0
d, 2x3 - 9x + 2 = 0
e, 8x3 - 4x2 + 10x - 5 = 0
a, 3x2 - 8x2 - 2x+3=0
2x(3-8) - 2x+3=0
2x5 - 2x+3=0
2x5 - 2x=0-3=
2x5 - 2x=-3
2x(5-x)=-3
5-x=-3/2
5-x=1,5
x=5-1,5
x=3,5
3,5 nha bn
chúc bn học tốt
happy new year
Biết rằng \left(x^{4}-4\right)\left(-2x^{3}+5x-3\right) = -2x^{7}+5x^{5}-3x^{4}+8x^{3}-20x+12(x4−4)(−2x3+5x−3)=−2x7+5x5−3x4+8x3−20x+12.
Kết quả phép nhân \left(-x^{4}+4\right)\left(-2x^{3}+5x-3\right)(−x4+4)(−2x3+5x−3) là ?
Bài 1. Phân tích các đa thức sau thành nhân tử:
a) 8x3-2x c) -5m3(m+1)+m+1
Bài 7. Tìm x, biết:
a) 2-x=2(x-2)3 b) 8x3-72x=0
d) 2x3+3x2+3+2x=0
Bài 1:
a: \(8x^3-2x=2x\left(4x^2-1\right)=2x\left(2x-1\right)\left(2x+1\right)\)
c: \(-5m^3\left(m+1\right)+m+1=\left(m+1\right)\left(-5m^3+1\right)\)
Bài 1: \(\dfrac{1}{3}\) + \(\dfrac{2}{4}\) + \(\dfrac{3}{5}\) ...........................3(>,<,=)
A.>
B.<
C.=
Bài 2: \(\dfrac{8x7-8x3}{8x2}\) = ?
A.2
B.3
C.4
D.5
Gỉai các phương trình sau;
a, 3x2 - 8x2 - 2x + 3 = 0
b, (x2 - 1)2 = 4x +1
c, 2x3 + 7x2 + 7x + 2 = 0
d, 2x3 - 9x + 2 = 0
e, 8x3 - 4x2 + 10x - 5 = 0
g. x3 + x2 - x√22 - 2√22= 0
h. (x +1 )2 = 9(x - 1)2