212009 is OBJECTIVE tyoe, options batao
How many distinct ordered pairs (x,y) exist where x and y are positive integers and satisfy xy = 72(x+y) ?
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341The diophantine \frac{1}{x} + \frac{1}{y} = \frac{1}{75} has solutions (75+n1, 75+n2) such where n1n2 = 752
So the problem is basically to find number of distinct ways of factoring 752 = 54X32 into two factors
21this is like finding two integral resistances whose parallele comb. gives Eq. Res. = 72
so x,y>72 is for sure...........
11
Explanation for n1n2 = 722
(x + y) 1
-------------- = ------ .....................(1)
xy 72
Let (x,y) be (72 + n1 , 72 + n2)
Subst. in (1) ,
2*72 + (n1 + n2) 1
------------------------------------ = ------
722 + 72(n1 + n2) + n1n2 72
2*722 + 72(n1 + n2) = 722 + 72(n1 + n2) + n1n2
Hence, n1n2 = 722
11722 = 26 x 34 x 1
Now the question becomes :
" Find the no. of ways in which six 2's , four 3's and one 1 can be divided into two groups such that both groups have at least one element. "
1bhaiyyya isn't it 1/72<1/x?. when x<72? .[7]......
and da last statement...m not able 2 get it[2]
1koi toh explain karo naa...muje samaj nahi aa raha hain...woh last step
62oh i deleted my post.. it was all crap.. sorry for confusing you aarthi...
1jeepers...[12] no pbs bhaiyaa ...by da by the last step is not clear to me can u explain it?