Use arccos...cos^-1 so
cos^-1 (0.8195)
it equals 34.96522689°
Tan(x)= sin(x)/cos(x), therefore, substitute sin(x)/cos(x) in the expression:
=(cos(x)(sin(x)/cos(x))-1)/cos^2(x)
simplify the 2 cos(x):
=(sin(x)-1)/cos^2(x)
Sin^2(x)+ cos^2(x)=1, sin^2(x)-1=- cos^2(x), substitute in the expression:
= -cos^2(x)/cos^2(x)= -1
Answer:
Neither.
Step-by-step explanation:
13 - 1 = 12 and 19 - 13 = 6 - no common difference so its not Arithmetic.
13/1 = 13 and 19/13 = 1.46 - no common ratio so its not Geometric.