Question

which of the following are NOT trigonometric identities, Check all that apply
a.) sec^(2) x - tan^(2) x=1
b) sec^(2) x+csc^(2) x=1
c) sin^(2) x + cos^(2) x=1
d) tan^(2) x + sec^(2) x =1

Answer 1

i was thinking of B

Answer 2

just b

Answer 3

a) and c) only are trignometric identities

Answer 4

Check them one by one:

a.\[\sec^{2} x - \tan^{2} x=\frac{ 1 }{ \cos^2x }-\frac{ \sin^2x }{\cos^2x }=\frac{ 1-\sin^2x }{ \cos^2x }=\frac{ \cos^2x }{ \cos^2x }=1\], so a. is true...

Answer 5

d is trigonometric too dude.

Answer 6

@darth How?