Question

Which represents the first three terms of the sequence: a1 = 2 and an = 5(an-1)2? 2, 20, 400
2, 20, 2000
2, 100, 2000
2, 100, 4000

Answer 1

$\bf \begin{array}{ll} term&value\\ \text{\textemdash\textemdash\textemdash}&\text{\textemdash\textemdash\textemdash}\\ a_1&2\\\\ a_2&5(a_{n-1})^2\\ &5(a_{2-1})^2\\ &5(a_1)^2\\ &5(2)^2\\ &20\\\\ a_3&5(a_{3-1})^2\\ &5(a_2)^2\\ &5(20)^2 \end{array}$