Giải:
\(-a^2\left(3a-5\right)+4a\left(a^2-a\right)\)
\(=-3a^3+5a^2+4a^3-4a^2\)
\(=\left(-3a^3+4a^3\right)+\left(5a^2-4a^2\right)\)
\(=a^3+a^2\)
\(=a^2\left(a+1\right)\)
Vậy ...
Giải:
\(-a^2\left(3a-5\right)+4a\left(a^2-a\right)\)
\(=-3a^3+5a^2+4a^3-4a^2\)
\(=\left(-3a^3+4a^3\right)+\left(5a^2-4a^2\right)\)
\(=a^3+a^2\)
\(=a^2\left(a+1\right)\)
Vậy ...
thuc hien phep tinh:
a) \(\dfrac{4}{x+2}+\dfrac{2}{x-2}+\dfrac{5x-6}{4-x}\)
thuc hien phep tinh:
a) \(\dfrac{4}{x+2}+\dfrac{2}{x-2}+\dfrac{5x-6}{4-x^2}\)
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)
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:
B=1/3+1/3^2+1/3^3+...+1/3^2004+1/3^2005
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 nhan:
(x+1)(1+x-x^2+x^3-x^4)-(x-1)(1+x+x^2+x^3+x^4)
thuc hien phep tinh:
a,\(1\dfrac{1}{2}\). \(2\dfrac{1}{3}\)+ \(1\dfrac{1}{3}\). \(\dfrac{1}{2}\)
b,\(\dfrac{1}{9}\).\(\dfrac{2}{145}\)\(-4\dfrac{1}{3}\). \(\dfrac{2}{145}\)+\(\dfrac{2}{145}\)