Hindi, asked by kavyamaheshwari38, 1 year ago

Please help me. I am asking though question 3 time but all answer are wrong. Please help me.

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Answers

Answered by devanayan2005
1

Given x = 9 + 4√5, find √x - 1 / √x

√x = √(9 + 4√5)

√x = √(√5 + √4 + 2√(5x4))

√x = √(√5 + √4)2  

√x = √5 + 2

1 / √x = 1 / (√5 + 2)  rationalize we get

1 / √x =  (√5 - 2)

∴ √x - 1 / √x = √5 + 2 - √5 + 2 = 4.

Hope helps

Pls mark brainliest

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devanayan2005: Brainliest pls
kavyamaheshwari38: Marked as brainlist
devanayan2005: Thx
kavyamaheshwari38: I Don't understand
kavyamaheshwari38: I am in 9th class only
devanayan2005: So 9th and 12th whatever rationalizing is rationalizing bro
kavyamaheshwari38: In starting I don't understand
kavyamaheshwari38: I know rationalising very well
kavyamaheshwari38: Starting meathod I don't understand
devanayan2005: Ok wait i will do simple wait
Answered by preetgoswami44
1

Solution

i) Given: x=(9-4√5) 

ii) ==> √x = √(9-4√5); let this = √a - √b 

Squaring both sides, 9 - 4√5 = a + b - 2√(ab) 

Equating the rational and irrational parts from both side, a+b = 9 and 2√(ab) = 4√5 

By identity, (a - b) = |√{(a+b)² - 4ab}| 

So, here (a - b) = |√(81 - 80)| = 1 

Solving (a + b) = 9 and (a - b) = 1, a = 5 and b = 4 

Thus, √x = √5 - 2 

iii) 1/√x = 1/(√5 - 2) = (√5 + 2) [By rationalizing the denominator] 

iv) Hence, √x + 1/√x = (√5 - 2) - (√5 + 2) = -4 

Square root symbol was found missing in these two steps, which now have been corrected. 

"By identity, (a - b) = |√{(a+b)² - 4ab}| 

So, here (a - b) = |√(81 - 80)| = 1"


preetgoswami44: okk then follow the first answer that have given by first person
preetgoswami44: Sorry
devanayan2005: Ok i will give you easy method write another question
devanayan2005: I am writtin JEE in 12th just finished
kavyamaheshwari38: Not another
kavyamaheshwari38: Same question
devanayan2005: Ok wait
devanayan2005: I will answer your first question but only in 1 promise mark me brainliest
preetgoswami44: please mark him as a brainliest
devanayan2005: It is already marked :)
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