Maclaurin

• TenSaru

  19 Mar 10, 01:12

  The maclaurin expansion for 1/ sqroot(1-x²) = 1+ x²/2 + (3x^4)/8 +...

  Question: Estimate the value for sqroot 3

  i subbed x = sqroot (2/3) in the equation and got 1.5 but the answer scheme sub x=1/2 and then rearrange to get 256/147... I know the answer scheme's answer is way closer to the actual value than mine. Is there anything wrong with my method?

  Thanks for helping!

• wee_ws

  19 Mar 10, 07:49

  Hi,

    Your method is alright, except that it is not a good approximation as compared to x = 1/2.

    Another possibility is to use the substitution x = -1/2.

    As you may observe, many substitutions may be possible. What really matters is how close we can get to the true value.

    Thanks.

  Cheers,
  Wen Shih