Proving GP Sum and Expanding Binomial Formula: 2n, 2x - 3y

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SUMMARY

The discussion focuses on three mathematical problems: finding the sum of a geometric progression (GP) with first term 1/2 and common ratio -1, proving the formula for the sum of the first n even numbers using mathematical induction, and expanding the binomial expression (2x - 3y)^4. The correct approach for the GP involves substituting the values into the formula for the sum of a GP. For the induction proof, the base case must be verified, and the assumption for n = k should be used to prove the case for n = k + 1. The binomial expansion requires careful attention to the coefficients and terms involved.

PREREQUISITES
  • Understanding of geometric progressions (GP) and their summation formulas.
  • Knowledge of mathematical induction and its application in proofs.
  • Familiarity with the binomial theorem for expanding expressions.
  • Basic algebraic manipulation skills for handling polynomial expressions.
NEXT STEPS
  • Study the formula for the sum of a geometric series, specifically for cases with negative ratios.
  • Learn the detailed steps of mathematical induction, including base case verification and inductive steps.
  • Explore the binomial theorem and practice expanding various binomial expressions.
  • Review algebraic techniques for simplifying and manipulating polynomial terms.
USEFUL FOR

Students in mathematics, educators teaching algebra and calculus, and anyone interested in mastering mathematical proofs and polynomial expansions.

r-soy
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3 – If r = -1 and frist term is 1/2 find the sum of the 10 terms of a Gp

4 - Use mathematical induction to prove that 2 + 4 + 6 ……..+ 2n = n(n+1)

5 – Expand ( 2x – 3y)^4 by using binomial formula

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D. Mark i can't type my work into the text entry box. i put it in attachment I'm very sorry
 

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3. S10 isn't 1/11. a1 = ? r = ? n = ? Substitute these values into your formula.
4. That's not how you do a proof by induction.
Show that the statement is true for some base case such as n = 1. (What does the formula look like if n = 1? Is it true for that case?)
Assume that the statement is true for n = k. (What does the formula look like for that case?)
Use your assumption in the previous step to show that the statement is true for n = k + 1.

5. You're sort of on the right track here, but you mixed up 2x by using 3x.
 

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