Question

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Answer 1

^use this

Answer 2

\[ \large 3=3\cdot1 \]
\[ \large 6=3\cdot2 \]
\[ \large 9=3\cdot3 \]+
do u see the pattern?

Answer 3

yes..

Answer 4

i dont know how to out it in sigma Notation though

Answer 5

your terms look like \(3k\) so it will be
\[\sum_{k=1}^n3k\] to figure out what \(n\) is , figure out how many terms you have