Question

Answer to my question correctly and I will donate 50 points​

Answer 1

very easy

answer is 38

like and give points for elaborate answrr

Answer 2

given x = 3 - 2√2

➡ x² = (3 - 2√2)²

by using identity (a - b)² = a² - 2ab + b²

➡ x² = (3)² - 2(3)(2√2) + (2√2)²

= 9 - 12√2 + 8

= 17 - 12√2

$\sf\frac{1}{ {x}^{2} } = \frac{1}{1 7 - 12 \sqrt{2} } \\ \\ \sf = \frac{1}{17 - 12 \sqrt{2} } \times \frac{17 + 12 \sqrt{2} }{17 + 12 \sqrt{2} } \\ \\ \sf = \frac{17 + 12 \sqrt{2} }{(17 - 12 \sqrt{2})(17 + 12 \sqrt{2} ) } \\ \\ \sf = \frac{17 + 12 \sqrt{2} }{( {17)}^{2} - ( {12 \sqrt{2} })^{2} } \\ \\ \sf = \frac{17 + 12 \sqrt{2} }{289 - 288} \\ \\ \sf = 17 + 12 \sqrt{2}$

now we know the values of x² and 1/x²

therefore x² - 1/x² = 17 - 12√2 - (17 + 12√2)

= 17 - 12√2 - 17 - 12√2

= -24√2 ( final answer )