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#1 Re: Help Me ! » Difficult equations » 2007-09-10 23:50:02

hi , The solution of this is simple
x^5 = 5y^3 - 4z
y^5 = 5z^3 - 4x
z^5 = 5x^3 - 4y


Since all three equations are rotational
like
x=y+z
y=x+z
z=x+y
That is they rotate from preceding equation
This implies
x=y=z

So just place y & z with x from any of the equation
x^5 = 5x^3 - 4x
=>x^5-5x^3 + 4x=0
=>x(x^4-5x^2 + 4)
=>x((x^2 -4)(x^2 -1))
=>Hence now it is easy I suppose
x=-2,-1,0,1,2 =y=z

You can take any value at the time and can verify

#2 Re: Help Me ! » solve » 2007-08-30 01:55:12

I think there is no integer solution other then 1


x^2+2^(x-1/x)-2^(2-1/x)

=>x^2=2^2*2^(-1/x)-2^x*2^(1/x)
on solving it gives

X^2=2^x-2^(x-1/x)/2^1/x

Since the denominator is 2^1/x  so other than 1 it would be non rational value..........

#3 Re: Help Me ! » How come?? » 2007-08-30 01:01:41

Lets do it step by step instead of using formula...

Since
In 2001 it would be

A2001=A2000-A2000*r/100
Hence A2001=A2000(1-r/100)

Similiarly A2002=A2001(1-r/100)

A2003=A2002(1-r/100)
A2004=A2003(1-r/100)=A2002(1-r/100)^2=A2001(1-r/100)^3=A2000(1-r/100)^4

Hence A2004=A2000(1-r/100)^4

This is from where actual formula arises..............
Benefit of doing step by step is like if rate changes every year.........r1,r2,r3,r4

Formula would be

A2004=A2000(1-r1/100)(1-r2/100)(1-r3/100)(1-r4/100)

#4 Help Me ! » identify defective coin? » 2007-08-30 00:48:23

kmadhyan
Replies: 4

HI Everyone...........


    You have 12 coins one of them is defective by weight,all are identical...(not known heavier or lighter)....

Using weight balance 3 times only can you identify defective coin...........

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