Tim n ∈\in∈ N de:
a) A= 5xnx^nxny3y^3y3 ⋮⋮⋮ B=4x3x^3x3 y
b) M=9x8x^8x8 yny^nyn ⋮⋮⋮ N=6x3x^3x3 y2y^2y2
CO GIUP MK VOI
∈\in∈
a )
Để A ⋮⋮⋮ B thì xn≥x3x^n\ge x^3xn≥x3 ⇒n≥3\Rightarrow n\ge3⇒n≥3
Để M ⋮⋮⋮ N thì yn≥y2⇒n≥2y^n\ge y^2\Rightarrow n\ge2yn≥y2⇒n≥2
tinh .
a,4^5:4^3
b,x^6:x^3
c,(-y)^6:y^5
mắt xích xe đạp gồm bao nhiêu mối ghép ? nói rõ từng loại mối ghép đó
Tìm x :
1, (x+1)3−(x−1)3=6⋅(x+2)2−9\left(x+1\right)^3-\left(x-1\right)^3=6\cdot\left(x+2\right)^2-9(x+1)3−(x−1)3=6⋅(x+2)2−9
2, (2x−1)⋅(4x2+2x+1)+(1−2x)3=3⋅(2x+3)2\left(2x-1\right)\cdot\left(4x^2+2x+1\right)+\left(1-2x\right)^3=3\cdot\left(2x+3\right)^2(2x−1)⋅(4x2+2x+1)+(1−2x)3=3⋅(2x+3)2
1, (3x+2)2−(2x−1)⋅(2x+1)=5⋅(x−2)2\left(3x+2\right)^2-\left(2x-1\right)\cdot\left(2x+1\right)=5\cdot\left(x-2\right)^2(3x+2)2−(2x−1)⋅(2x+1)=5⋅(x−2)2
2, (x+2)2−(x+3)⋅(x−1)=5x\left(x+2\right)^2-\left(x+3\right)\cdot\left(x-1\right)=5x(x+2)2−(x+3)⋅(x−1)=5x
3, (3x−1)⋅(x−3)+(x−2)2=(2x−5)2\left(3x-1\right)\cdot\left(x-3\right)+\left(x-2\right)^2=\left(2x-5\right)^2(3x−1)⋅(x−3)+(x−2)2=(2x−5)2
Tìm x: x2−2x=24x^2-2x=24x2−2x=24
Tìm x: (2x+1)2−(1−2x)2=16\left(2x+1\right)^2-\left(1-2x\right)^2=16(2x+1)2−(1−2x)2=16
Tìm GTNN của: N = (x2−4x−5).(x2−4x−19)+49\left(x^2-4x-5\right).\left(x^2-4x-19\right)+49(x2−4x−5).(x2−4x−19)+49
Tớ cần gấp, các cậu giúp tớ với!
Tìm x
a, (x−5)⋅(x+5)−(x+3)2=2x−3\left(x-5\right)\cdot\left(x+5\right)-\left(x+3\right)^2=2x-3(x−5)⋅(x+5)−(x+3)2=2x−3
b, (2x+3)2+(x−1)⋅(x+1)=5⋅(x+2)2\left(2x+3\right)^2+\left(x-1\right)\cdot\left(x+1\right)=5\cdot\left(x+2\right)^2(2x+3)2+(x−1)⋅(x+1)=5⋅(x+2)2
Tìm GTLN của:
2x−2x2−52x-2x^2-52x−2x2−5
(7+2x)(49-14x+4x2)
(x+2)(x2-2x+4)
27x3-8
(7-x)(49+7x+x2)
(x-5)(x2+5x+25)