Question

Use a fatoração e calcule
a) 9999( elevado a 2 ) - 9998 ( elevado a 2
b ) 3123091 ( elevado a 2 ) - 3123090 ( elevado a 2 )

Answer 1

Resposta:

a)

${a}^{2} - {b}^{2} = (a - b) \times (a + b) \\ {9999}^{2} - {9998}^{2} = (9999 - 9998) \times (9999 + 9998) \\ = 1 \times 19997 = 19997$

b)

$3123091 {}^{2} - {3123090}^{2} = (3123091 - 3123090) \times (3123091 + 3123090) \\ = 1 \times 6246181 = 6246181$