Question

the sum of a number and it's reciprocal is 5 .then find sum of number and it's reciprocal. ​

Answer 1

Correct Question:

The sum of a number and it's reciprocal is 5 . Find the number and it's reciprocal. ​

Let the required number = x

Its Reciprocal is = $\dfrac{1}{x}$

Given:

$x + \dfrac{1}{x} = 5$

Multiplying by x throughout, we get:

x² + 1 = 5x

⇒ x² - 5x + 1 = 0

We cannot Factorise the above Equation.

So, We use 'Quadratic Formula' to find the value of 'x'

x² - 5x + 1 = 0 is of the form ax² + bx + c = 0 where a = 1; b = -5; c = 1

x = $\dfrac{-b \pm \sqrt{b^2 - 4ac} }{2a}$

⇒ x = $\dfrac{- (-5) \pm \sqrt{(-5)^2 - 4(1)(1)} }{2(1)}$

⇒ x = $\dfrac{5\pm \sqrt{25 - 4} }{2}$

⇒ x = $\dfrac{5 \pm \sqrt{21} }{2}$

Answer:

x = $\dfrac{5 \pm \sqrt{21} }{2}$    and       $\dfrac{1}{x} = \dfrac{2}{5 \pm \sqrt{21} }$

Answer 2

Step-by-step explanation:

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Q. Wʜᴀᴛ ɪs ᴛʜᴇ ᴘʟᴀᴄᴇ ᴠᴀʟᴜᴇ ᴏғ 5 ɪɴ 150 ?

$\huge\underline\frak\blue{Aɴsᴡᴇʀ:-}$

Tʜᴇ ᴘʟᴀᴄᴇ ᴠᴀʟᴜᴇ ᴏғ 5 ɪɴ 150 ɪs 10 ᴛʜ ᴘʟᴀᴄᴇ.

Tʜᴀɴᴋ ʏᴏᴜ ☺✌..