Correct question:
a sequence U1, U2,U3...... is defined by the relation [tex]U_{n +1} = 2U_n +5[/tex]. if U1 =2, find U2 and U3
Answer:
U2 = 9
U3 = 23
Step-by-step explanation:
Given sequence;
[tex]U_{n +1} = 2U_n +5[/tex]
U1 = 2
U2 = ?
[tex]U_{n +1} = 2U_n +5\\\\U_2 = 2(U_1) + 5\\\\U_2 = 2(2) + 5\\\\U_2 = 4 + 5\\\\U_2 = 9[/tex]
Solving for U3;
[tex]U_3 = 2(U_2) + 5\\\\U_3 = 2(9) + 5\\\\U_3 = 18 + 5\\\\U_3 = 23[/tex]