Question

¿Me ayudan con dos problemas matemáticos?

Answer 1

a)

$\frac{1}{m} + \frac{1}{n} = 8 \: \: \: \: \: \: \frac{1}{mn} = 8$

...

$\frac{1}{m} + \frac{1}{n} = 8 \\ \frac{m + n}{mn} = 8 \\( m + n)( \frac{1}{mn} ) = 8 \\ (m + n) \times 8 = 8 \\ m + n = 1 \\ \frac{m + n}{8} = \frac{1}{8}$

b)

$f(x) = 2x - 5$

...

$f(x - 3) = 2(x - 3) - 5 \\ f(x - 3) = 2x - 6 - 5 \\ f(x - 3) = 2x - 11$