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Answers to exam review

asmith42

Here are my answers for the exam review:

1a. {4 \choose 2}
1b. {{4 \choose 1}\cdot{4 \choose 1}}
2. {52 \choose 5}
3. \sum_{k=0}^{100}{100 \choose k}({2x^2})^{100-k}({-3y^3})^{k}
4a. {10 \choose 2}
4b. {13 \choose 2}
5a. {19 \choose 3}
5b. {23 \choose 3}
6. {a_n}={3n^2}-{2n}
7. {a_n}=(1/2)(2)^n+(1/2)(4)^n
8a. {13 \choose 5}
8b. {40 \choose 20}