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what is remainder when 6^17 +17^6isdividedby7?
Read Solution (Total 5)
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- It is divisible by 7, so rem will be 0.
for 6^17/7=(-1)^17/7=-1
Rem cant be a negetive. so 7-1=6 is rem.
for 17^6/7=(3)^6/7=(27)^2/7=(-1)^2/7=1/7
So rem for second part is 1.
if we add both rems
6+1=7 i.e. absolutely divisible by 7. so rem will be 0
- 10 years agoHelpfull: Yes(14) No(5)
- 0(ans)
6^17/7=(7-1)^17/7 = (-1)^17/7 = -1
rem is -ve so 7-1=6 is rem.
for 17^6/7 = (14+3)^6/7 = (3)^6/7 = (9)^3/7 = (7+2)^3/7 = (2)^3/7 = (8)/7
(7+1) /7= 1/7
so rem for 2nd part is =1 and of 1st part is =6
total rem. = 1+6=7
so 7/7=0 - 10 years agoHelpfull: Yes(6) No(1)
- 6^(x) unit digit 6
17^(6)= 1st time 17*17=unit digit -9
and next unit digits are 3,1,7,9
so 6+9=15
15/7=1 remainder - 10 years agoHelpfull: Yes(3) No(1)
- it can be solved as:
[(7-1)^17+(14+3)^6]/7=[(-1)^17+(3)^6]/7=-1+[(3^2)^3]/7=-1+1=0
- 10 years agoHelpfull: Yes(0) No(0)
- (7-1)^17+(14+3)^6
=(-1)^17+(3^3*3^3)
=-1+(28-1)*(28-1)
=-1+(-1*-1)
=0/7
Remainder 0 - 10 years agoHelpfull: Yes(0) No(0)
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