tìm x:
2x* (x-1^7)=0
chinh bay ro rang gium minh nha
Tim x biet :
a, |2x+1|-x=5
b, |x-10|10+|x-11|10=1
Trinh bay cach lam ro rang cho minh nhe
Chieu phai nap roi
Ai trinh bay ro rang nhat minh se tick
\(\left|2x+1\right|-x=5\)
\(\Rightarrow2x+1-x=5\)
\(\Rightarrow x+1=5\)
\(\Rightarrow x=5-1\)
\(\Rightarrow x=4\)
C(x)= -2x^2 + mx - 7m + 3
da thuc C(x) co nghiem la -1
Cac ban giai ra ro rang gium minh nhe
Tim x,y biet (x+2).(3-x)>0 ......(cac ban trinh bay ro rang giup minh nha)
cho bz - cy /a = cx - az /b = ay - bx /c
chung minh rang x/a = y/b = z/c
MAY BAN LM GAP BAI NAY GIUM MIK TRC NHE! GIAI RO RANG CHI TIET RA NHE.MIK CAN GAP
Ta có : \(\frac{bz-cy}{a}=\frac{cx-az}{b}=\frac{ay-bx}{c}\)
= \(\frac{abz-acy}{a^2}=\frac{bcx-abz}{b^2}=\frac{acy-bcx}{c^2}=\frac{abz-acy+bcx-abz+acy-bcx}{a^2+b^2+c^2}=0\)
=> \(\frac{bz-cy}{a}=0\)nên bz - cy = 0 => bz = cy.Hay b/y = c/z [1]
=> \(\frac{cx-az}{b}=0\)nên cx - az = 0 => cx = az . Hay c/z = a/x [2]
Từ 1 và 2 => \(\frac{x}{a}=\frac{y}{b}=\frac{z}{c}\)
a)(27+65)+(346-27-65)
b)(42-69+17)-(42+17)
Trinh bay ro tung buoc gium minh nha
a. (27 + 65) + (346 - 27 - 65)
= 27 + 65 + 346 - 27 - 65
= (27 - 27) + (65 - 65) + 346
= 0 + 0 + 346
= 346
b. (42 - 69 + 17) - (42 + 17)
= 42 - 69 + 17 - 42 - 17
= (42 - 42) + (17 - 17) - 69
= 0 + 0 - 69
= -69
chắc bạn k cần cách thuận tiện nhất nhỉ
a) ( 27 + 65 ) + ( 346 - 27 - 65 )
= 92 + 254
= 346
b) ( 42 - 69 + 17 ) - ( 42 + 17 )
= -10 - 59
= -69
chắc bạn k cần cách thuận tiện , nếu bạn cần ns mình mình làm cho
a) (27+65)+(346-27-65)
= 27+65+346-27-65
= (27-27)+(65-65)+346
= 0+0+346
= 346
b) (42-69+17)-(42+17)
= 42-69+17-42-17
= (42-42)+(17-17)-69
= 0+0-69
= -69
Tick nha
1, tim x
5+x-3=5-(x+4)
x-(5|-7|+3)=|-8|+6-2
|x-3|+7
12-3|x-1|=6
cac ban giup minh nhe nho cac buoc tinh ro rang nha minh se like cho
\(5+x-3=5-\left(x+4\right)\)
\(5+x-3=5-x-4\)
\(x+x=5-4-5+3\)
\(2x=-1\)
\(x=\frac{-1}{2}\)
vay \(x=\frac{-1}{2}\)
\(x-\left(5.\left|-7\right|+3\right)=\left|-8\right|+6-2\)
\(x-\left(5.7+3\right)=8+6-2\)
\(x-38=12\)
\(x=12+38\)
\(x=50\)
vay \(x=50\)
\(\left|x-3\right|+7=0\)
\(\left|x-3\right|=-7\)( ko ton tai)
\(12-3\left|x-1\right|=6\)
\(3\left|x-1\right|=6\)
\(\left|x-1\right|=2\)
\(\Rightarrow\orbr{\begin{cases}x-1=2\\x-1=-2\end{cases}}\Rightarrow\orbr{\begin{cases}x=3\\x=-1\end{cases}}\)
vay \(\orbr{\begin{cases}x=3\\x=-1\end{cases}}\)
Phan tich da thuc thanh nhan tu:
1) P=125x^3 -8y^3
2) P= 4x(x-2y+8y(2y-x)
3) (2x+1)^2 - (x-1)^2
Cac ban ghi loi giai ro rang cho minh nha
P= 125x^3-8y^3
=5^3x^3-2^3y^3
=(5x)^3-(2y)^3
=(5x-2y)(25x^2+10xy+4y^2)
P=4x(x-2y)+8y(2y-x)
=4x(x-2y)-8y(x-2y)
=(4x-8y)(x-2y)
=4(x-2y)(x-2y)
=4(x-2y)^2
(2x+1)^2-(x-1)^2=(2x+1-x+1)(2x+1+x-1)
=(x+2)3x
K NHA!
Tìm nghiệm đa thức : f(x)=3x3-27x. Trinh bay ro giup minh nha.
f(x)=0
<=> \(3x^3-27x\)\(=0\)
=>\(x\left(3x^2-27\right)=0\)
TH1: x=0
TH2: x=3
2017+|2017-x|=x. Tìm x
giai ro rang nha////
\(2017+\left|2017-x\right|=x\)
\(\Leftrightarrow\left|2017-x\right|=x-2017\)
\(\Leftrightarrow x\ge2017\)