Question 723968


{{{a[n] = a[1]+(n-1)d}}}

{{{a[12] = 6+(12-1)3}}}

{{{a[12] = 6+11*3}}}

{{{a[12] =39}}}


check:

if {{{n=1}}}

{{{6 = 6+(1-1)3}}}

{{{6 = 6+(0)3}}}

{{{6 = 6}}}....first term is correct, {{{a[1] =6}}}

if {{{n=2}}}

{{{a[2] = 6+(2-1)3}}}

{{{a[2] = 6+3}}}

{{{a[2]=9}}}....... {{{a[2] =9}}}

if {{{n=3}}}

{{{a[3] = 6+(3-1)3}}}

{{{a[3] = 6+6}}}

{{{a[3]=12}}}....... {{{a[3] =12}}}

if {{{n=4}}}

{{{a[4] = 6+(4-1)3}}}

{{{a[4] = 6+9}}}

{{{a[4]=15}}}....... {{{a[4] =15}}}
:
:
:
if {{{n=12}}}

{{{a[12] = 6+(12-1)3}}}

{{{a[12] = 6+33}}}

{{{a[12]=39}}}....... {{{a[12] =39}}}