Answer:
Step-by-step explanation:
1) 1 , -3 , 9 , -27 , 81 ,...........
It is Geometric sequence
ratio = 2 term ÷ first term = -3 ÷ 1 = -3
1st term = 1
2nd term = 1 * -3 = -3
3rd term = -3 *(-3) = 9
4th term = 9 *(-3) = - 27
6th term = 81 *(-3) = -243
7th term = -243 *(-3) = 729
8th term = 729 *(-3) = -2187
Next 3 terms: - 243 , 729 , - 2187,....
4)
[tex]\frac{1}{2}, \frac{1}{2} , \frac{3}{8} , \frac{1}{4} ,\frac{5}{32},.....\\\\\\Rule = \frac{n}{2^{n}}\\Term1 = \frac{1}{2^{1}}=\frac{1}{2}\\\\Term2 = \frac{2}{2^{2}}=\frac{2}{4}=\frac{1}{2}\\\\Term3 = \frac{3}{2^{3}}=\frac{3}{8}\\\\Term4 = \frac{4}{2^{4}}=\frac{4}{16}=\frac{1}{4}\\\\Temr5 = \frac{5}{2^{5}}=\frac{5}{32}\\\\Term6 = \frac{6}{2^{6}} = \frac{6}{64} = \frac{3}{32}\\\\Term7 = \frac{7}{2^{7}}=\frac{7}{128}\\\\Term8 =\frac{8}{2^{8}} = \frac{8}{256}=\frac{1}{32}\\\\[/tex]
Next 3 terms are : 3/32 , 7/128 , 1/32
