Question

calcule o 20 termo da PA (26, 31, 36, 41)

Answer 1

a₁ = 26
a₂ = 31
n = 20
r = 31 - 26 = 5
       a₂₀ = a₁ + (n - 1) * r
       a₂₀ = 26 + (20 - 1) * 5
       a₂₀ = 26 + 19 * 5
       a₂₀ = 26 + 95
       a₂₀ = 121

Espero ter ajudado. Valeu!
       

Answer 2

$a_n=a_1+(n-1)\cdot r$

$a_{20}=26+(20-1)\cdot5$

$a_{20}=26+19\cdot5$

$a_{20}=26+ 95$

$\red{\boldsymbol{ a_{20}= 121}}$