Question

if x=[5/7]^-5*[7/5]^-7 then find 2x+1

Answer 1

$x = ( \frac{5}{7} ) {}^{ - 5} \times ( \frac{7}{5} ) {}^{ - 7} \\ = ( \frac{7}{5} ) {}^{5} \times ( \frac{5}{7} ) {}^{7} \\ = \frac{7}{5} \times \frac{7}{5} \times \frac{7}{5} \times \frac{7}{5} \times \frac{7}{5} \times \frac{5}{7} \times \frac{5}{7} \times \frac{5}{7} \times \frac{5}{7} \times \frac{5}{7} \times \frac{5}{7} \times \frac{5}{7} \\ \frac{5 \times 5}{7 \times 7} = \frac{25}{49}$
2x +1 = 2 \times \frac {25}. {49}+ 1
\frac {50}{49}+1 =
I hope you understand answer.

Please mark as brilliant answer.

Answer 2

$<b> Given that X =$
$= { (\frac{5}{7} )}^{- 5} \times ( { \frac{7}{5}) }^{ - 7 } \\ \\ = ( { \frac{7}{5} )}^{5} \times {( \frac{5}{7}) }^{7} \\ \\ = { (\frac{5}{7} )}^{2} \\ \\ = \frac{25}{49}$
now as
X = 25 / 49

then 2X + 1

$= 2 \times \frac{25}{49} + 1 \\ \\ = \frac{50}{49} +1 \\ \\ = \frac{99}{49}$
${\bold{\blue{Hope\: it\: helps}}}$