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Spec: PRF5 · No calculator · ~150s
Letters only — the answer key is hidden. Work it out, then check the solution below.
No written hint yet — check the trope: chain-transitivity. Name the trap first, work the stem by hand, then open the solution below.
Same topic · same level
TMUA-P2-PRF5-001
A proof reads: (1) Let m = 2j and n = 2k be even integers. (2) Then m + n = 2j + 2k = 2(j + k). (3) Hence the sum is eve…
Following proofs
Same trap: chain-transitivity
TMUA-P2-PRF5-007
Let P be “ n is divisible by 24 ”, Q be “ n is divisible by 8 ”, and R be “ n is divisible by 4 ”. Since 24 = 8 × 3 and…
Following proofs
Step up a level
TMUA-P2-PRF5-002
A proof that the square of an odd integer is odd reads: (1) Write n = 2k + 1. (2) Then n^2 = 4k^2 + 4k + 1. (3)??? (4) H…
Following proofs