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1. Find the formula for each sequence, assuming the pattern shown continues. 5 3 (a) {-3, 2, -4' 4' 7 (c) {-1, 0, 1, 0, -1, 0, 1...} (b) {1, 1, 2, 3, 5, 8, ...} (d) {-1, 3, -3, 5, -5, ...} 2. Let an = cos2 (n) 2n . Prove that the sequence converges and find the limit