hi everyone
Compute for the following:
if
my working:
start from a1= 0=0(0+1)(0+2)=0
a2=1=1(1+1)(1+2)=6
a3=2=2(2+1)(2+2)=24
a4=3=3(3+1)(3+2)=60
a5=4=4(4+1)(4+2)=120
answer :210
i am confused wheter the answer is 210 or 420. i started with a1(0) until a5(4).
i am confused,please advise. did i do it right,
thank you so much for your advice.
thank you in advance.