2ax^2-a(1+2x^2)-[a-x(x+a)]
=2ax2-2ax2+a+x2-ax+a
=(2ax2-2ax2)-(a+a)+ax+x2
=0-2a+ax+x2
=x2+ax-2a
2ax^2-a(1+2x^2)-[a-x(x+a)]
=2ax2-2ax2+a+x2-ax+a
=(2ax2-2ax2)-(a+a)+ax+x2
=0-2a+ax+x2
=x2+ax-2a
rut gon bieu thuc sau
A=5x-2-/2x+1/
1 rut gon bieu thuc ; A=5Ix+1I-3.[4-2x]
Cho x/a =y/b =z/c va a b c x y z khac 0 rut gon bieu thuc b = ( a^2x + b^2y + c^2z ) / x^3 +y^3+z^3
Rut gon bieu thuc
(x+1)2 - (x-1)2 - 3. (x+1). (x-1)
Rut gon bieu thuc ( 2x like )
a)28^15 . 3^17
_____________
84^16
b) 3^10 + 6^2
________________
5.3^8 + 20
voi a<-1, gia tri rut gon cua bieu thuc /a/ +a la............
Rut gon bieu thuc
B= 3.(-1)-2.\(|\)x+3\(|\)
Rut gon bieu thuc ( 2x like )
a)28^15 . 3^17
_____________
84^16
b) 3^10 + 6^2
________________
5.3^8 + 20
Rut gon bieu thuc ( 2x like )
a)28^15 . 3^17
_____________
84^16
b) 3^10 + 6^2
________________
5.3^8 + 20