Question

DADA LA SUCESIÓN 3/4, 1/2, 1/4 ....
Comprueba de forma razonada que es una p.a
Halla su termino general y calcula a76

Answer 1

Respuesta:

a_{n} = a_{1} + (n-1)*d\\\\a_{3} = a_{1} + (3-1)*d\\\\\frac{1}{4}  = \frac{3}{4} + (3-1)*d\\\\\frac{1}{4}  = \frac{3}{4} + 2d\\\\\- 2d= \frac{3}{4} - \frac{1}{4}\\\\

d= (2/4)/-2

d= -\frac{1}{4}

a_{n} = a_{1} + (n-1)*d

a_{n} = \frac{3}{4}  + (n-1)*-\frac{1}{4}

a_{n} = -\frac{n-4}{4}

a_{76} = \frac{3}{4}  + (76-1)*-\frac{1}{4}

a_{76}= -18

Explicación paso a paso: