Math, asked by aksh173, 1 year ago

rationalise......please solve this question......please..

Attachments:

Answers

Answered by divu20
1
i hope it to be correct.....
Attachments:

aksh173: ok as you wish
Mankuthemonkey01: no
Mankuthemonkey01: 4+√15 is correct
divu20: how
Mankuthemonkey01: when u take 30 as common in the bracket there should be 4 not 40
aksh173: yes ur ans is correct bro
divu20: oh!! i got it just wait a second
aksh173: thanks a lot
Mankuthemonkey01: Yep
Mankuthemonkey01: Welcome @aksh
Answered by Mankuthemonkey01
6
To rationalize, here we should multiply the denominator by 5√3 +3√5 as well as numerator.

So
 \frac{5 \sqrt{3  }  + 3 \sqrt{5} }{5 \sqrt{3}  - 3 \sqrt{5} }  \times  \frac{5 \sqrt{3} + 3 \sqrt{5}  }{5 \sqrt{3} +  3\sqrt{5}  }  \\
I'm the denominator we can use the identity
(a + b)(a -b ) = a² - b²
and in numerator we can use (a +b)² = a² + b² + 2ab

=>
 \frac{(5 \sqrt{3} + 3 \sqrt{5}) {}^{2}   }{(5 \sqrt{3} ) {}^{2}  - (3 \sqrt{} 5) {}^{2} }  \\  =  \frac{25 \times 3 + 9 \times 5 + 2 \times 5 \sqrt{3 } \times 3 \sqrt{5}  }{25 \times 3 - 9 \times 5}  \\  =  \frac{75 + 45 + 30 \sqrt{15} }{75 - 45}  \\  =  \frac{120 + 30 \sqrt{} 15}{30}  \\  =  \frac{30 (4 + 1 \sqrt{15} )}{30}
now cancelling 30 with 30 we get

4 + 1 \sqrt{15}
=
4 +  \sqrt{15}
Hope it helps dear friend ☺️✌️

Anonymous: mayank kon? xD
aksh173: ya nice answer
Mankuthemonkey01: Thanks Both Bhai
aksh173: he is a genius
Anonymous: oops,sorry, ,Nice answer Manku xD
Mankuthemonkey01: @aksh thise two are more genius than me
Mankuthemonkey01: xD
aksh173: ya you 3 are genius
Mankuthemonkey01: xD thanks from all 3
QGP: Well Done!! Just a tip: You can add new line in the Tex Code by adding \\ wherever you would like a new line in the formula. When you increase spacing, the formulas will look more elegant :)
Similar questions