The sequence u_1, u_2, u_3, ... , is defined by the recurrence relation u_{n+1} = (-1)^n u_n + d, u_1 =2, where d is a constant. Show that u_5 = 2

Step 1: Before going to do the problem, Find the knowns and unknowns in and note it down.
Step 2: Explore the given rule
EXAMPLE: x_{n+1} = ax_n - 3
Succeeding term = a (preceding term) - 3
Step 3: By using the given rule find the required terms (x_2, x_3,x_4...etc)
NOTE: According to the given rule substitute the values to get the required
term.
EXAMPLE: For an attempt to find the x_3
x_{n+1} = ax_n - 3
x_3=ax_2-3
Substitute the values x_2 [ Calculate x_2(x_2=a-3,\ take\ x_1=1 since n>1)]
x_3 = a(a - 3) - 3
x_3 = a^2 – 3a – 3
Step 4: Compare the result with the given answer, verify is it equating or not