Question

find the value
$x + 1 | x = 3 evaluate x {2} + 1 |x }^{2}$
please help me​

Answer 1

EXPLANATION.

⇒ (x + 1/x) = 3.

As we know that,

Squaring on both sides of the equation, we get.

⇒ (x + 1/x)² = (3)²

⇒ x² + 1/x² + 2(x)(1/x) = 9.

⇒ x² + 1/x² + 2 = 9.

⇒ x² + 1/x² = 9 - 2.

⇒ x² + 1/x² = 7.

                                                                                                               

MORE INFORMATION.

(1) (a + b)² = a² + 2ab + b².

(2) (a - b)² = a² - 2ab + b².

(3) (a² - b²) = (a - b)(a + b).

(4) (a² + b²) = (a + b)² - 2ab.

(5) (a + b)³ = a³ + 3a²b + 3ab² + b³.

(6) (a - b)³ = a³ - 3a²b + 3ab² - b³.

(7) (a³ - b³) = (a - b)(a² + ab + b²).

(8) (a³ + b³) = (a + b)(a² - ab + b²).