A = 2x2 - 3 . |x| + 1
+ Thay x = 2 vào biểu thức A, ta được:
A = 2 . 22 - 3 . |2| + 1
A = 2 . 4 - 3 . 2 + 1
A = 8 - 6 + 1
A = 2 + 1
A = 3
Vậy giá trị của biểu thức A tại x = 2 là 3.
Mình chỉ làm câu A thôi nhé bạn.
Chúc bạn học tốt!
Tìm x,biết
a, \(\frac{3}{\left(x+2\right)\left(x+5\right)}+\frac{5}{\left(x+5\right)\left(x+10\right)}+\frac{7}{\left(x+10\right)\left(x+17\right)}=\frac{x}{\left(x+2\right)\left(x+17\right)}\)
Với x ∉ -2,-5,-10,-17
b,\(\frac{2}{\left(x-1\right)\left(x-3\right)}+\frac{5}{\left(x-3\right)\left(x-8\right)}+\frac{12}{\left(x-8\right)\left(x-20\right)}-\frac{1}{x-20}=\frac{-3}{4}\)
Với x∉1,3,8,20
c,\(\frac{x-1}{2009}+\frac{x-2}{2008}=\frac{x-3}{2007}+\frac{x-4}{2006}\)
1) \(\left|x+1\right|=\left|x+3\right|\)
2) \(\left|x+2\right|+\left|x+3\right|=3.x+3\)
3) \(\left|x+1\right|+\left|x+2\right|=4\)
1) \(\left|3x+2\right|=\left|x+1\right|\)
2) \(\left|\left(x+2\right)\times x\right|=\left|x+2\right|\)
3) \(\left|2x+3\right|=x+1\)
4) \(\left|4x+5\right|+3.x=7\)
Bài 1 : Tìm \(x,y,z\in Q\)
\(a)\left|x-3,5\right|+\left|4,5-y\right|=0\)
\(b)\left|x-2\right|+\left|3-y\right|=0\)
\(c)\left|x+\frac{2}{3}\right|+\left|y-\frac{3}{4}\right|+\left|z-5\right|=0\)
\(d)\left|x+\frac{13}{14}\right|+\left|x-\frac{3}{7}\right|=0\)
giúp mình với ❤❤❤
a)\(\left(x-\frac{2}{3}\right)\). \(\left(x+\frac{1}{4}\right)\)= 0
b) \(\left(x-\frac{2}{3}\right)\). \(\left(2x-\frac{3}{4}\right)\) = \(\left(3x+\frac{1}{2}\right)\). \(\left(x+\frac{2}{3}\right)\)
tìm x;y
b \(\left|x-y\right|+\left|y+\dfrac{9}{25}=0\right|\)
c \(\left(\dfrac{1}{2}x-5\right)^{20}+\left(y^2-\dfrac{1}{4}\right)^{10}=0\)
a \(\left|\dfrac{1}{2}-\dfrac{1}{3}+x\right|=\dfrac{-1}{4}-y\)
d \(\left|x\left(x^2-\dfrac{5}{4}\right)\right|=x\) \(\left(x\ge0\right)\)
e \(x^2+\left(y-\dfrac{1}{10}\right)^4=0\)
4, tìm x biết;
a, \(\left|x-1\right|+\left|x-3\right|=4\)
b. \(\left|2x-1\right|+\left|x+2\right|=3\)
Tìm x, y, z:
a) \(\left|x+\dfrac{19}{5}\right|+\left|y+\dfrac{1890}{1975}\right|+\left|z-2005\right|=0\)
b) \(\left|x+\dfrac{3}{4}\right|+\left|y-\dfrac{1}{5}\right|+\left|x+y+z\right|\) = 0
c) \(\dfrac{16}{2^x}=1\)
d) \(\left(2x-1\right)^3=-27\)
e) \(\left(x-2\right)^2=1\)
f) \(\left(x+\dfrac{1}{2}\right)^2=\dfrac{4}{25}\)
g) \(\left(x-1\right)^2=\left(x-1\right)^6\)
5. Tìm x biết:
a, \(\left|x+1\right|+\left|x+2\right|+\left|x+3\right|+...+\left|x+10\right|=11x+1\)
b, \(\left|x+\frac{1}{101}\right|+\left|x+\frac{2}{101}\right|+...+\left|x+\frac{100}{101}\right|=101x\)
