PLEASE HELP ME!!!!!!

Answer:
[tex] \huge \red{ c_3 = - 1}[/tex]
Step-by-step explanation:
[tex]c_1 = 1 \\ \\
c_n= - 2c_{n-1}+5 \\ \\ c_2 = - 2c_{2-1}+5 \\ \\ c_2 = - 2c_{1}+5 \\ \\ c_2 = - 2(1)+5 \\ \\ c_2 = - 2+5 \\ \\ \huge \purple{c_2 =3} \\ \\ c_3 = - 2c_{3-1}+5 \\ \\ c_3 = - 2c_{2}+5 \\ \\ c_3 = - 2(3)+5 \\ \\ c_3= - 6+5 \\ \\ \huge \red{ c_3 = - 1}[/tex]