assume that f(1)=0 and f(m+n)=f(m)+f(n)+4(9mn-1).for all natural no(integer>0)m and n.what is the value of f(17)?

• 4832...
  calculate upto f(5)by putting values in the given expression i.e. f(1)=0, f(2)=32, f(3)=100, f(4)=204, f(5)=344. then cal f(7)=f(5+2)orf(3+4)=732 and f(10)=f(5+5)=1584, and now f(17)=f(10+7)=f(10)+f(7)+4(9*15*7 -1)..........
  f(17)=1584+732+2516=4832
• 10 years agoHelpfull: Yes(70) No(5)
• f(2) = f(1+1)=f(1)+f(1)+4(9*1*1 - 1 )= 0+0+4*8 = 32
  f(4) = f(2+2)=f(2)+f(2)+4(9*2*2 - 1 )= 32+32+4*35 = 204
  f(8) = f(4+4)=f(4)+f(4)+4(9*4*4 - 1 )= 204+204+4*143 = 980
  f(16) = f(8+8)=f(8)+f(8)+4(9*8*8 - 1 )= 980+980+4*575 = 4260
  f(17)= f(1+16)= f(16)+f(1)+4(9*16*1 -1)= 4260+0+ 4*143= 4832
• 10 years agoHelpfull: Yes(64) No(2)
• f(2) = f(1+1)=f(1)+f(1)+4(9*1*1 - 1 )= 0+0+4*8 = 32
  f(4) = f(2+2)=f(2)+f(2)+4(9*2*2 - 1 )= 32+32+4*35 = 204
  f(8) = f(4+4)=f(4)+f(4)+4(9*4*4 - 1 )= 204+204+4*143 = 980
  f(16) = f(8+8)=f(8)+f(8)+4(9*8*8 - 1 )= 980+980+4*255 = 2980
  f(17)= f(1+16)= f(1)+f(16)+4(9*16*1 -1)= 0+ 2980 + 4*143= 3552
• 10 years agoHelpfull: Yes(13) No(12)
• 4(9-1)+4(9*2-1)+4(9*3-1)+........+4(9*16-1)
  4[9(1+2+3+.....+16)-16]
  4[9*16*17/2-16]
  4832
• 10 years agoHelpfull: Yes(6) No(0)
• f(16+1)=f(16)+f(1)+4((9*16*1)-1)=f(16)+0+(4*143)
  f(16)=f(15+1)=f(15)+0+(4*((9*16*1)-1)
  .....
  f(2)=f(1+1)=f(1)+f(1)+(4((1*1*9)-1)
  therefore series formed will be
  f(17)=4*((9*1)+(9*2)+(9*3)..........(9*16))
  f(17)=4832
• 10 years agoHelpfull: Yes(3) No(1)
• f(2) = f(1+1)=f(1)+f(1)+4(9*1*1 - 1 )= 0+0+4*8 = 32
  f(4) = f(2+2)=f(2)+f(2)+4(9*2*2 - 1 )= 32+32+4*35 = 204
  f(8) = f(4+4)=f(4)+f(4)+4(9*4*4 - 1 )= 204+204+4*143 = 980
  f(16) = f(8+8)=f(8)+f(8)+4(9*8*8 - 1 )= 980+980+4*575 = 4260
  f(17)= f(1+16)= f(16)+f(1)+4(9*16*1 -1)= 4260+0+ 4*143= 4832
• 9 years agoHelpfull: Yes(3) No(0)
• 1047..by f(9+8)
• 10 years agoHelpfull: Yes(1) No(3)
• f(1)=0, f(2)=32, f(3)=100, f(4)=204, f(5)=344.
  
  f(17)=1584+732+2516=4832. Ans
• 10 years agoHelpfull: Yes(1) No(0)
• Unit digit is 6.
• 10 years agoHelpfull: Yes(0) No(4)
• ans will be 5032
• 10 years agoHelpfull: Yes(0) No(11)
• answer is 6
• 10 years agoHelpfull: Yes(0) No(9)