(tim x biet (x+1)(2-x)-(3x+5)(x+2)=-4x^2+1
tim x biet:
( x^2-4x+16 )( x+4 )-x ( x+1 )(x+2)+3x^2=0
(8x+2)(1-3x)+(6x-1)(4x-10)=-50
5/ Tim x,y,z biet
a/x^2+2y^2+2xy-2y+1=0
b/5x^2+3y^2+2^2-4x+6xy+4z+6=0
tim x biet 4x2 -12x-7=0
tim x biet x2-11x+18=0
-4x2+5x-1=0 2x3+3x2+2x+3=0x(2x-7)-4x+14=0tinh nhanh bt sau
A=3.(x-3).(x+7)+(x-4)2+48,tai x=0.5
(4x+1)(1-4x+16x^2) - 16x(4x^2-5) = 17 tim x
Tim x biet:
a) 5x2 . ( 2x - 3 ) + ( 2x2 + 3x + 3 ) . ( 3 - 2x ) = 6x3 - 9x2
b) ( 4x2 + 2x ) . ( x2 - x ) + ( 4x2 + 6 ) . ( x - x2 ) = 0
Tim x biet:
a) ( 3x -5 )2 - ( 3x + 1 )2 = 8
b) 2x . ( 8x - 3 ) - ( 4x - 3 )2 = 27
1)Tim MAX cua A= (6x^2-2x+1)/ x^2
2)tim MIN va MAX C= (3-4x)/(X^2+1)
3) Tim MIN va MAX P = x^2+y^2
biet giua x va y co moi quan he nhu sau : 5x^2+8xy+5y^2=36
4)tim MAX Q = -x^2-y^2+xy+2x+2y
