Results 1 to 2 of 2

Math Help - I collected questions from different papers and I tried to solve them by myself and

  1. #1
    Senior Member
    Joined
    Oct 2009
    Posts
    290

    I collected questions from different papers and I tried to solve them by myself and

    Hi

    I collected questions from different papers and I tried to solve them by myself and I want to correct them
    Attached Thumbnails Attached Thumbnails I collected questions from different papers and I  tried to solve them by myself and-2.jpg   I collected questions from different papers and I  tried to solve them by myself and-3.jpg   I collected questions from different papers and I  tried to solve them by myself and-4.jpg  
    Follow Math Help Forum on Facebook and Google+

  2. #2
    MHF Contributor
    Grandad's Avatar
    Joined
    Dec 2008
    From
    South Coast of England
    Posts
    2,570
    Hello r-soy

    (1) d = 3. Correct.

    S_{51} = \frac{51}{2}\Big(2(3)+50(\color{red}3\color{black}  )\Big) = 3978

    (2) The algebra in the induction proof is not complete. You need to say:
    \tfrac13(4k^3-k)+(2(k+1)-1)^2 = \tfrac13(4k^3-k)+(2k+1)^2
    =\tfrac13(4k^3-k+3[4k^2+4k+1])

    =\tfrac13(4k^3+12k^2+11k+3)

    =\tfrac13(4k^3+12k^2+12k+4-[k+1])

    =\tfrac13(4[k+1]^3-[k+1])
    (3) Again, your working is not complete:
    \left(\frac{y}{x}\right)^{k+1}=\left(\frac{y}{x}\r  ight)^{k}\cdot\frac{y}{x}
    =\frac{y^k}{x^k}\cdot\frac yx

    =\frac{y^{k+1}}{x^{k+1}}
    Grandad
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. Replies: 0
    Last Post: July 19th 2010, 10:30 AM
  2. Fourier Transform in Describing Collected Data
    Posted in the Advanced Statistics Forum
    Replies: 0
    Last Post: March 3rd 2010, 02:33 PM
  3. Replies: 4
    Last Post: July 19th 2008, 07:18 PM

Search Tags


/mathhelpforum @mathhelpforum