thuc hien phep tinh roi tinh gia tri bieu thuc
x(x2-y)-x2(x+y)+y(x2-x)
tai x=2012
y=1/5
tim x biet,
5x + 5x+2= 650
Thuc hien phep tinh
(1+2+3+4+...+90).(12.34 - 6.68) : (1/3+1/4+1/5+1/6)
thuc hien phep tinh:
a,2xyz+4xyz-\(\dfrac{1}{2}\)xyz
b,\(\dfrac{x^2}{2}\)+\(\dfrac{x^2}{3}\)+\(\dfrac{x^2}{4}\)
thuc hien phep tinh (1-1/(1+2)).(1-1/(1+2+3))...(1-1/(1+2+3+...+2006))
1/2.x2.y2(2x+y).(2x-y)
Thuc hien phep tinh
a;1/2-1/3.7-1/7.11-1/11.15 -1/15.19-1/19.23-1/23.27 thuc hien phep tinh
thuc hien phep tinh 1/100x99 - 1/99x98 - ........- 1/3x2 - 1/2x1
thuc hien phep tinh:
P=(1/2-1*1/3-1*1/4-1*...1/2017-1*1/2018-1)
Thuc hien phep tinh:
B=1/3+1/3^2+1/3^3+...+1/3^2004+1/3^2005