Question

given that 180¡ã¡ÜA¡Ü 270¡ãand tan A=3/7,
what is the exact value of cos A?


can someone please help ???i need to know how to solve it !
thanks!

Answer 1

On my screen, it is symbols gone mad, I can't decipher your meaning. Can you type it in standard ASCII?

common symbols > greater than
=> equal or greater than

Answer 2

"given that 180¡ã¡ÜA¡Ü 270¡ãand tan A=3/7,
what is the exact value of cos A? "

where you saying something like

given that 180º < A < 270º and tan A=3/7,
what is the exact value of cos A?

if so, then consider a right-angled triangle with a vertical of 3 and a horizontal of 7 in the first quadrant, angle A at the origin.
then clearly tan A = 3/7
by Pythagoras the hypotenuse is √(3^2 + 7^2)
=√58
then cos A = 7/√58 if the angle is in the first quadrant

but your angle is in the third quadrant, where the cosine is negative

So the exact value of cos A = -7/√58

Answer 3

thanks!