Question

plzz ans it fast.........​

Answer 1

Answer:

d) NOTA

Step-by-step explanation:

y= √2 +1

y+1/y

= (√2+1) +1/(√2+1)

= (2+2√2+1+1)/(√2+1)

= (4+2√2)/(√2+1)

= [2√2(√2+1)]/(√2+1)

= 2√2

d. NOTA

Answer 2

Required Answer:-

Given:

• y = √2 + 1

To find:

• The value of y + 1/y

Solution:

Here,

$\rm y = \sqrt{2} + 1$

$\rm \implies \dfrac{1}{y} = \dfrac{1}{\sqrt{2} + 1}$

$\rm \implies \dfrac{1}{y} = \dfrac{1( \sqrt{2} - 1) }{(\sqrt{2} + 1)( \sqrt{2} - 1 )}$

$\rm \implies \dfrac{1}{y} = \dfrac{ \sqrt{2} - 1 }{2 - 1}$

$\rm \implies \dfrac{1}{y} = \sqrt{2} - 1$

Therefore,

$\rm y + \dfrac{1}{y}$

$\rm = \sqrt{2} + 1 + \sqrt{2} - 1$

$\rm = 2\sqrt{2}$

Hence,

$\rm \implies y + \dfrac{1}{y} = 2 \sqrt{2}$

Hence, none of the options is correct.

Answer:

$\rm \implies y + \dfrac{1}{y} = 2 \sqrt{2}$