Question

progressão aritmética 

Answer 1

A
$a_{n} = a_{1}+ (n-1)r$
$a_{5} = a_{1}+ (5-1)r$
$a_{1}= -5$
$r=6$
$a_{5} = a_{1}+ (5-1)r$
$a_{5} = -5+ (5-1)6$
$a_{5} = -5+ 4*6$
$a_{5} = -5+ 24$
$a_{5} = 19$
Pa = crescente

B
$a_{n} = a_{1}+ (n-1)r$
$a_{5} = a_{1}+ 4r$
$a_{1}=8$
$r=6$
$a_{5} = 8+4*6$
$a_{5} = 8+24$
$a_{5} = 32$
Pa = crescente

C
$a_{n} = a_{1}+ (n-1)r$
$a_{5} = a_{1}+ (5-1)r$
$a_{1}=19$
$r=-6$
$a_{5} = 19+4*-6$
$a_{5} = 19-24$
$a_{5} = -5$
Pa = decrescente


D
$a_{n} = a_{1}+ (n-1)r$
$a_{5} = a_{1}+ (5-1)r$
$a_{1}=33$
$r=0$
$a_{5} = 33+4*0$
$a_{5} = 33+0$
$a_{5} = 33$
Pa = constante

2
$a_{n} = a_{1}+ (n-1)r$
$a_{37} = a_{1}+ (37-1)r$
$a_{1}=1$
$r=6$
$a_{37} = a_{1}+ 36r$
$a_{37} = 1+ 36*6$
$a_{37} = 217$