Question

Find cos A if b=9,c=15.

Answer 1

this sounds like cosine law....

Answer 2

Is that the whole question?

Answer 3

or is it a^2 +b^2=c^2 ??

Answer 4

..........from the fig. we are getting a = 12 this means given triangle satisfy pythagoras theorem.....so angle opp. i.e. angle C= 90 degree. so using cosA =9/15