40 lines
558 B
TeX
40 lines
558 B
TeX
\beginsection{7.1}
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Write out the first five terms of the following sequences.
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\medskip
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(a) $s_n=1/(3n+1)$
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\medskip
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$s_1={1\over4}$,
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$s_2={1\over7}$,
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$s_3={1\over10}$,
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$s_4={1\over13}$,
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$s_5={1\over16}$
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\medskip
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(b) $b_n=(3n+1)/(4n-1)$
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\medskip
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$b_1={4\over3}$,
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$b_2={7\over7}$,
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$b_3={10\over11}$,
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$b_4={13\over15}$,
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$b_5={16\over19}$
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\medskip
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(c) $c_n=n/3^n$
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\medskip
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$c_1={1\over3}$,
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$c_2={2\over9}$,
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$c_3={3\over27}$,
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$c_4={4\over81}$,
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$c_5={5\over243}$
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\medskip
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(d) $\sin(n\pi/4)$
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\medskip
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$\sqrt2\over2$,
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$1$,
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$\sqrt2\over2$,
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$0$,
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$-{\sqrt2\over2}$
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