Question

rationalise the dinomerator 4/7+4√3​

Answer 1

sorry no spam but you've posted this question under english category. better post according to the type of question so that people who are good in english will filter their page to english. and they will only answer english.

Answer 2

answer

$\frac{4}{7 + 4 \sqrt{3} }$

$\frac{4}{7 + 4 \sqrt{3} } \times \frac{7 - 4 \sqrt{3} }{7 - 4 \sqrt{3} }$

$\frac{4(7 - 4 \sqrt{3)} }{ {7 }^{2} - {(4 \sqrt{3}) }^{2} }$

by using identity (a+b) × (a-b ) =

${a}^{2} - {b}^{2}$

$\frac{28 - 16 \sqrt{3} }{49 - (16 \times 3)}$

$\frac{28 - 16 \sqrt{3} }{49 - 48}$

$\frac{28 - 16 \sqrt{3} }{1}$

$28 - 16 \sqrt{3}$

answer is

$28 - 16 \sqrt{3}$