Violympic toán 8
Các câu hỏi tương tự
Giải phương trình:
x-1001/1006 + x-1003/1004 + x-1005/1002 + x-1007/1000 = 4
giải hương trình:\(\dfrac{x-1001}{1006}+\dfrac{x-1003}{1004}+\dfrac{x-1005}{1002}+\dfrac{x-1007}{1000}\)=4
Chứng minh các hằng đẳng thức sau :
a, left(a^2-b^2right)+left(2abright)^2left(a^2+b^2right)^2
b, left(a^2+b^2right).left(c^2+d^2right)left(ac+bdright)^2+left(ad-bcright)^2
c, left(ax+bright)^2+left(a-bxright)^2+c^2x^2left(a^2+b^2+c^2right).left(x^2+1right)
d, dfrac{1}{2}.left(a+b+cright).left[left(a-bright)^2+left(b-cright)^2+left(c-aright)^2right]a^3+b^3+c^3-3abc
e, 1000^2+1003^2+1005^2+1006^21001^2+1002^2+1004^2+1007^2
Đọc tiếp
Chứng minh các hằng đẳng thức sau :
a, \(\left(a^2-b^2\right)+\left(2ab\right)^2=\left(a^2+b^2\right)^2\)
b, \(\left(a^2+b^2\right).\left(c^2+d^2\right)=\left(ac+bd\right)^2+\left(ad-bc\right)^2\)
c, \(\left(ax+b\right)^2+\left(a-bx\right)^2+c^2x^2=\left(a^2+b^2+c^2\right).\left(x^2+1\right)\)
d, \(\dfrac{1}{2}.\left(a+b+c\right).\left[\left(a-b\right)^2+\left(b-c\right)^2+\left(c-a\right)^2\right]=a^3+b^3+c^3-3abc\)
e, \(1000^2+1003^2+1005^2+1006^2=1001^2+1002^2+1004^2+1007^2\)
Tìm x biết :
a) x2\(-\)4x+4=25
b) \(\dfrac{x-17}{1990}\)+\(\dfrac{x-21}{1986}\)+\(\dfrac{x+1}{1004}\)=4
c) 4x\(-\)12.2x+32=0
Cho:
\(\dfrac{x^4}{a}+\dfrac{y^4}{b}=\dfrac{1}{a+b}\) và \(x^2+y^2=1.\)
CMR:
\(\dfrac{x^{2004}}{a^{1002}}+\dfrac{y^{2004}}{b^{1002}}=\dfrac{2}{\left(a+b\right)^{102}}\)
Tìm x
a) x^3 - 16x = 0
b) x^4 - 2x^3 + 10x^2 - 20x = 0
c) (2x - 3 )^2 = (x+5)^2
d) x^2(x-1) - 4x^2 + 8x - 4 = 0
e) x^2 + 4x + 3 = 0
f) x^3 - x^2 = 4x^2 - 8x + 4
g) 2(x+3) - x^2 - 3x = 0
Tìm x:
a) 2x (x-5) -(x2-10x +25)=0
b) x2 - 9 +3x(x+3) = 0
c) x3 - 16x = 0
d) (2x+3)(x-2) - (x2 -4x+4) = 0
e) 9x2 -(x2 -2x +1)=0
f)x3-4x2 -9x +36 = 0
g) 3x - 6 = (x-1).(x-2)
i) (x-2).(x+2) +(2x+1)2 =-5x.(x-3) =5
k) x2 -1 = (x-1).(2x+3)
l) (2x-1)2 +(x+3).(x-3) -5x(x-2)=6
Tìm x biêt :
a. ( x + 3)2 + ( x - 2).( x + 2) - 2. ( x - 1)2 = 7
b. 36x2 - 4g = 0
c. ( x + 3) . ( x2 - 3x + g) - x . ( x - 1 ) . ( x + 1) - 27 = 0
d. x2 - 4x + 3 = 0
e. x . ( 2x -1 ) - ( x- 2) . ( 2x + 3) = 0
g. ( x - 1 ) . ( x + 2) - x - 2 = 0
mong jup dỡ ạ
1. 6x(x - 10) - 2x+200 6. 3x2 - 6x+30
2. 3x2(x - 3) + 3(3 - x)0 7. 4x2 - 10x+20
3. x2 - 8x+162(x -4) 8. x2 - 12x -180
4. x2 - 16 + 7x ( x+4)0 9. 3x2 - 10x+30
5. x2 - 13x - 140 10. 5x2 - 10x+100
Đọc tiếp
1. 6x(x - 10) - 2x+20=0 6. 3x2 - 6x+3=0
2. 3x2(x - 3) + 3(3 - x)=0 7. 4x2 - 10x+2=0
3. x2 - 8x+16=2(x -4) 8. x2 - 12x -18=0
4. x2 - 16 + 7x ( x+4)=0 9. 3x2 - 10x+3=0
5. x2 - 13x - 14=0 10. 5x2 - 10x+10=0