Question

If tanA =√3-1÷√3+1
then : COSA =??​

Answer 1

Answer:

sorry bro i don't have idea that

Answer 2

Answer:

$tan \:a = \frac{ \sqrt{3} - 1}{ \sqrt{3} + 1} \\ by \: rationlising \\ = \frac{ \sqrt{3} - 1}{ \sqrt{3} + 1} \times \frac{ \sqrt{3} - 1}{ \sqrt{3} - 1 } \\ = \frac{( \sqrt{3} - 1) ^{2} }{ ({ \sqrt{3} )}^{2} - 1 } \\ = \frac{3 + 1 - 2 \times \sqrt{3} \times 1}{3 - 1} \\ = \frac{4 - 2 \sqrt{3} }{2} \\ = 2 - \sqrt{3} \\ now \:$

tan theta = ✓1- sec^2 theta

sec theta = ✓1+tan^2 theta

by solving this we got the value of sec theta ,

then , sec theta = 1/ cos theta.