12:2+12x2=?
tinh nhanh
{125xa-125:a}x{1+2+3..........+9+10}=
12x4+12x2+12+12=
\(12\times4+12\times2+12+12\)
\(=12\times4+12\times2+12\times1+12\times1\)
\(=12\times\left(4+2+1+1\right)\)
\(=12\times8\)
\(=96\)
tính bằng cách thuận tiện nhất 5/12x2/3+ 2/3x7/12 +1/3
=(5/12+7/12)*2/3+1/3
=1*2/3+1/3
=2/3+1/3
=1
tính thuân tiện
5/12x2/3+2/3x7/12+1/3
5/12 x 2/3 + 2/3 x 7/12 + 1/3
= 2/3 x ( 5/12 + 7/12 ) + 1/3
= 2/3 x 1 + 1/3
= 2/3 + 1/3
= 1
5/12x2/3+2/3x7/12+1/3
=2/3x(5/12+7/12)+1/3
=2/3x1+1/3
=2/3+1/3
=1
k tui nha @@@
\(\frac{5}{12}\)x \(\frac{2}{3}\)+ \(\frac{2}{3}\)x \(\frac{7}{12}\)+ \(\frac{1}{3}\)
= \(\frac{2}{3}\)x ( \(\frac{5}{12}\)+ \(\frac{7}{12}\) ) + \(\frac{1}{3}\)
= \(\frac{2}{3}\)x 1 + \(\frac{1}{3}\)
= \(\frac{2}{3}\)+ \(\frac{1}{3}\)
= 1
a) 1,62 + 4 . 0,8 . 3,4 +3,42
b) x4 - 12x3 + 12x2 -12x +111
c) (x2+3)2 - (x+2)(x-2)(x2+12)
\(a,=1,6^2+2\cdot1,6\cdot3,4+3,4^2=\left(1,6+3,4\right)^2=5^2=25\\ b,Sửa:x^4-12x^3+12x^2-12x+11\\ =x^4-11x^3-x^3+11x^2+x^2-11x-x+11=x^3\left(x-11\right)-x^2\left(x-11\right)+x\left(x-11\right)-\left(x-11\right)\\ =\left(x-11\right)\left(x^3-x^2+x-1\right)=\left(x-11\right)\left(x-1\right)\left(x^2+1\right)\\ c,=\left(x^2+3\right)^2-\left(x^2-4\right)\left(x^2+12\right)\\ =x^4+6x^2+9-x^4-8x^2+48=-2x^2+57\)
Tính = cách thuận tiện nhất:
5/12x2/3+2/3x7/12+1/3
2/3x(5/12+7/12)+1/3
2/3x 1 +1/3
2/3+1/3
=1 k mik nhaaaaa
5/12×2/3+2/3×7/12+1/3
=2/3×(5/12+7/12)+1/3
=2/3× 1 +1/3
= 2/3 +1/3
= 1
\(\frac{5}{12}.\frac{2}{3}+\frac{2}{3}.\frac{7}{12}+\frac{1}{3}\)
\(=\frac{2}{3}.\left(\frac{5}{12}+\frac{7}{12}\right)+\frac{1}{3}\)
\(=\frac{2}{3}.\frac{12}{12}+\frac{1}{3}\)
\(=\frac{2}{3}.1+\frac{1}{3}\)
\(=\frac{2}{3}+\frac{1}{3}\)
\(=\frac{3}{3}=1\)
Dấu "." bằng dấu x
-5/12x2/11+-5/11x9/11+5/12
\(\dfrac{-5}{12}\times\dfrac{2}{11}+\dfrac{-5}{11}\times\dfrac{9}{11}+\dfrac{5}{12}\\ =\dfrac{5}{12}\times\left(1-\dfrac{2}{11}\right)+\dfrac{-5}{11}\times\dfrac{9}{11}\\ =\dfrac{5}{12}\times\dfrac{9}{11}+\dfrac{-5}{11}\times\dfrac{9}{11}\\ =\dfrac{9}{11}\times\left(\dfrac{5}{12}-\dfrac{5}{11}\right)\\ =\dfrac{9}{11}\times\dfrac{-5}{132}=-\dfrac{15}{484}\)
-5/12x2/11+-5/12x9/11+5/12
giúp mình với
A = \(\dfrac{-5}{12}\)x\(\dfrac{2}{11}\)+\(\dfrac{-5}{12}\)x\(\dfrac{9}{11}\)+\(\dfrac{5}{12}\)
A= \(\dfrac{-5}{12}\)(\(\dfrac{2}{11}\)+\(\dfrac{9}{11}\)-1)
A = 0
Hàm số y = 1 4 x 4 + 1 3 x 3 - 1 2 x 2 - x - 12 đồng biến trên khoảng nào
A. ( - ∞ ; - 1 )
B. ( - 1 ; 0 )
C. ( 0 ; 1 )
D. ( 1 ; + ∞ )
Tìm số nghiệm nguyên của bất phương trình 1 2 x 2 - x - 12 > 1 2 x - 1
A. 7
B. 9
C. 8
D. 10