(x-2)(x+2) = x2 - 4
22 - 4 = 0
=> x \(\ge\)2
(x-2)(x+2) = x2 - 4
22 - 4 = 0
=> x \(\ge\)2
Tìm x ϵ Z:
a) 86 : [2. (2x + 1)2 - 7] + 42 = 2 . 32
b) 20 - [42 + (x - 6)] = 90
c) 1000 : [30 + (2x - 6)] = 32 + 42
d) (x + 11) ⋮ (x + 2) , x ϵ N
Giúp mk với !!
Tìm các số nguyên x biết
a . x + 2 − 7 = 0 b . 2 x + x = 3 x c . 17 − x + x − 4 = 0 d . x − 7 + x − 7 = 0
tìm x biết :
a,(2x+ 4/5) (3x-1/2)= 0
b,(x-2/5) (x+4/7)= 0
c,-1 =|x- 5/6|= 1/2
d,x+ 5/8 x- 12/16x= 1
tìm x
a) (5-x).(x-1)<0
b) (x-4).\(\left(x+\dfrac{1}{2}\right)>hoặc=0\)
tìm x,ythuôc z:a)/x-1/.(y mủ 2+1)
b)y mủ 2./x-3/=4
Tìm x, y ∈ Z:
a) \(\dfrac{4}{x}\)=\(\dfrac{y}{-21}\)=\(\dfrac{28}{49}\).
b) \(\dfrac{x}{7}\)=\(\dfrac{9}{y}\) , x > y.
c) \(\dfrac{x}{15}\)=\(\dfrac{3}{y}\) , x < y < 0
Tìm x Z:
a) −1+3−5+7−...+x=200; b) −4+6−8+...−x=−400
1. Chứng tỏ rằng:
P = 1/11 + 1/12 + 1/13 +...+1/70 < 5/2
2. Tìm x \(\in\)Z biết:
a) (x + 7).(x + 4) < 0
b) (2x + 3).(x - 5) \(\ge\)0
GIÚP MÌNH NHA MN!!! LÀM HẾT MÌNH TICK CHO!!!
1) Tìm x biết:
a) ( -3)( 2 - x) - 3(x - 1) = 2x + 3 b) (2x - 10)( x2 + 1) = 0
c) ( x + 1)( 2x - 6) = 0 d) ( x2 + 1)( x - 2) > 0 e) ( - x2 - 1)( 3 - x) \(\ge\) 0
2) Tìm x,y \(\in\) Z biết: xy + 2x + 2y = - 9