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n is a natural number and n^3 has 16 factors then how many factors can n^4 have?
Read Solution (Total 7)
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- The correct answer will be 25
suppose n^3= a^3*b^3
Therefore by using formula to know total factors (3+1)*(3+1)=4*4=16 as it was given in question only...
Now by using above concept we can write..
n^4 = c^4*d^4
so we will get (4+1)*(4+1) = 25 - 11 years agoHelpfull: Yes(40) No(4)
- 21 or 25
16 = 1*8 or 4*4
=> n^3 is of the form a^15 or a^3 * b^3
1) If n^3 = a^15 => n^4 = a^20
=> Number of factors = 21
2) If n^3 = a^3 * b^3 => n^4 = a^4 * b^4
=> Number of factors = 25 - 11 years agoHelpfull: Yes(10) No(10)
- If n = 2^5 => n^3 = 2^15 which has 16 factors
=> n^4 = 2^20
=> 21 factors
- 11 years agoHelpfull: Yes(2) No(2)
- if n^3 has 16 factors
then n^4 has to have 17 factors
e.i one extra factor
this extra factor is n^4 itself.
we can seed examples using small values for n like 2,3... - 11 years agoHelpfull: Yes(1) No(9)
- 21
n^3=16 factors(1+3(5factors)) - 11 years agoHelpfull: Yes(1) No(1)
- it will be 17 n^2 means n*n
why r u guys getting it complex - 11 years agoHelpfull: Yes(1) No(1)
- hi kunal ....aj ka puzzle banaya :)
- 11 years agoHelpfull: Yes(0) No(6)
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