Finding Angles of A Triangle Using Trigonometric Ratios

NOTE:   On the forum calc    tan^-1 is    atan

inverse tan is the same as arc tan!

1) Since cot = 1/tan ---> tan = 1/cot

     Thus cot A = 8/15 ---> tan A = 15/8 --> A = invtan(15/8)

     Enter (2nd) tan(15/8) ---> A = 10.77°.

 

2) Since cos = 1/sec  --> sec =1/cos

    Thus sec A = 17/8 ---> cos A = 8/17 ---> A = invcos(8/17)

    Enter (2nd) cos(8/17) ---> A = 61.93°