Sửa đề: \(\dfrac{4}{x+2}+\dfrac{2}{x-2}+\dfrac{5x-6}{4-x^2}\)
\(=\dfrac{4x-8+2x+4-5x+6}{\left(x-2\right)\left(x+2\right)}=\dfrac{x+2}{\left(x-2\right)\left(x+2\right)}=\dfrac{1}{x-2}\)
thuc hien phep tinh:
a) \(\dfrac{4}{x+2}+\dfrac{2}{x-2}+\dfrac{5x-6}{4-x^2}\)
thuc hien phep tinh:
a, 1\(\dfrac{1}{2}\).\(2\dfrac{1}{3}\)+1\(\dfrac{1}{3}\).\(\dfrac{1}{2}\)
b, \(\dfrac{1}{9}\).\(\dfrac{2}{145}\)-4\(\dfrac{1}{3}\).2\(\dfrac{2}{145}\)+\(\dfrac{2}{145}\)
thuc hien phep tinh:
a,\(1\dfrac{1}{2}\). \(2\dfrac{1}{3}\)+ \(1\dfrac{1}{3}\). \(\dfrac{1}{2}\)
b,\(\dfrac{1}{9}\).\(\dfrac{2}{145}\)\(-4\dfrac{1}{3}\). \(\dfrac{2}{145}\)+\(\dfrac{2}{145}\)
thuc hien phep tinh:
(x+2)(1+x-x^2+x^3-x^4)-(1-x)(1+x+x^2+x^3+x^4)
thuc hien phep tinh:
(x+2)(1+x-x^2+x^3-x^4)-(1-x)(1+x+x^2+x^3+x^4)
thuc hien phep tinh :
a, (x+1)(1+x-x^2+x^3-x^4)-(x-1)(1+x+x^2+x^3+x^4)
b, (2b^2-2-5b+6b^3)(3+3b^2-b)
Tìm GTLN của biểu thức: \(A=\left(\dfrac{x^2}{x^2-3x+2}+\dfrac{x^2}{x^2-5x+6}\right):\dfrac{x^4+x^2+1}{x^2-4x+3}\)
Tìm GTLN của biểu thức: \(A=\left(\dfrac{x^2}{x^2-3x+2}+\dfrac{x^2}{x^2-5x+6}\right):\dfrac{x^4+x^2+1}{x^2-4x+3}\)
Rut gon va tinh gia tri bieu thuc
A= (x-4).(x-2)-(x-1).(x-3) tại x= \(1\dfrac{3}{4}\)
