Respuesta :

Answer:

See explanation

Step-by-step explanation:

It should be 9x² not x²

p = (3x + 1) and q = (3x - 1)

pq + 1 = (3x + 1)(3x - 1) + 1

= (9x² - 3x + 3x - 1) + 1

= (9x² - 1) + 1

= 9x² - 1 + 1

= 9x²

Therefore,

pq + 1 = 9x²