Question

please answer
help me​

Answer 1

Answer:

3

Step-by-step explanation:

 $(x+\frac{1}{x}) ^{2}$ = $x^{2} +\frac{1}{x}^{2}$$+2$

      $(x+\frac{1}{x}) ^{2} = 7+2$

      $(x+\frac{1}{x})^{2} =9$

      $x+\frac{1}{x} =3$

       

Answer 2

2)

(7x+ 1/2 ) ( 7x− 1/2 ) = 49x^2 − b

b⇒49x^2 − 4/1 = 49x^2 − b

(∵ (a−b) (a+b) = a^2 − b^2)

2)⇒b= 4/1

1Option C is correct.