Question

Questão 1:
a) a soma dos 10 primeiros termos da PA (2, 5)​

Answer 1

$\mathsf{(2,5..)}\\\mathsf{a_{10}=a_{2}+8r}\\\mathsf{a_{10}=5+8.3=5+24=29}$

$\mathsf{S_{10}=\dfrac{10(2+29)}{2}}\\\mathsf{S_{10}=5.31\to}\large\boxed{\boxed{\boxed{\boxed{\mathsf{S_{10}=155}}}}}$