- **Algebra**
(*http://mymathforum.com/algebra/*)

- - **terms**
(*http://mymathforum.com/algebra/151-terms.html*)

termsfind the third term of (2x - 3y^2)^5 |

The third term will be 5C3a^3b^2 = 10*(2x)^3*(-3y)^2 =720x^3y^2 If you don't understand why, feel free to ask, but be specific to give us the best chance of giving you useful information. |

Quote:
how did you get 5c3a^3b^2 and arrive at that answer? |

5C3 refers to the "combination function." nCr=n!/[r!(n-r)!] where n! (pronounced "n factorial")=n(n-1)(n-2)(n-3)...*3*2*1 for all natural numbers n, and 0!=1. In (a+b)^n, the k^th term is always nCk[a^(n-k)b^k]. Note that nCr is undefined if r>n, because (-1)! makes no sense. |

oh i see thank you so very much |

All times are GMT -8. The time now is 07:42 PM. |

Copyright © 2019 My Math Forum. All rights reserved.