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How is the base case P(1)P(1) verified for the conjecture 2+42 + 4 + ... + 2n=n(n+1)2n = n(n+1)?

To verify the base case, substitute n=1n=1 into both sides of the equation. The left-hand side (LHS) becomes the first term, 2. The right-hand side (RHS) becomes 1(1+1)1(1+1), which simplifies to 2. Since LHS equals RHS, P(1)P(1) is true.

Conditions

  • The proposition is P(n)P(n): 2+42 + 4 + ... + 2n=n(n+1)2n = n(n+1).
  • The base case is checked at n=1n=1.

Reasoning, step by step

  1. Identify the LHS for n=1n=1: The sum contains only the first even integer, so LHS = 2.
  2. Identify the RHS for n=1n=1: Substitute n=1n=1 into n(n+1)n(n+1) to get 1(1+1)1(1+1).
  3. Simplify the RHS: 1(1+1)=1(2)=21(1+1) = 1(2) = 2.
  4. Compare LHS and RHS: 2=22 = 2.
  5. Conclude that P(1)P(1) is true.

Example

The video shows: 'P(1)P(1)_LHS = 2' and 'P(1)P(1)_RHS = 1(1+1)=21(1+1) = 2'. The narrator states, 'Since both sides equal 2, the base case is verified.'

Common misconceptions

  • Calculating the LHS as the sum of all terms up to 2n without setting n=1n=1.
  • Forgetting to simplify the RHS correctly.

Watch the explanation

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Answers are generated from source material and independently checked. Consult the original video or creator if something is unclear.