Question

What is the value........

Answer 1

Answer:

$a_5 = 120$

Step-by-step explanation:

Given

$a_1 = 1$

$a_n = n(a_{n-1})$

Required

$a_5$

This is calculated as:

$a_5 = 5(a_{5-1})$

$a_5 = 5*a_4$

Calculate $a_4$

$a_4 =4(a_{4-1})$

$a_4 =4*a_3$

Calculate $a_3$

$a_3 =3*a_2$

Calculate $a_2$

$a_2 = 2 * a_1$

$a_2 = 2 * 1$

$a_2 = 2$

So:

$a_3 =3*a_2$

$a_3 = 3 * 2 = 6$

So:

$a_4 =4*a_3$

$a_4 = 4 * 6 =24$

Lastly;

$a_5 = 5*a_4$

$a_5 = 5 * 24$

$a_5 = 120$