Answer:
Not sure of the rest but hope this helps
Answer:
an = 1/2 (n) (n+1)
Step-by-step explanation:
1,3,6,10,.........
3-1=2
6-3=3
Each term is different so there is no common difference. It is not an arithmetic sequence
3/1=3
6/3 =2
Each term is different so there is no common ratio. It is not a geometric sequence
1 3 6 10
+2 +3 +4
a1 = 1
a2 = 3
a3 = 6 = 2*3
a4 = 10 = 2*5
Using Pythagoras’ theorem a2 + b2 = c2 you can find out the third (longest) side. (6x6) + (8x8) = 100 (the square root of 100 is 10) so ur final sum is 6+8+10 = 24 mm
try that then times it by 12.1
