Questions LLC
Login
or
Sign Up
Ask a New Question
Trigonometry
Trigonometric Identities
Half-angle Identities
Use half angle indentites to find an exact value without a calculator
Cos(11π/12)
1 answer
this is a 15º reference angle in Quad II
15 is half of 30
You can
ask a new question
or
answer this question
.
Related Questions
half angle formula to find exact value
cos 112.5 degree
Use a double or half angle identity to find the exact value of the following expression: if cos x= 4/5 and 270° < x < 360°,
4. Find the exact value for sin(x+y) if sinx=-4/5 and cos y = 15/17. Angles x and y are in the fourth quadrant.
5. Find the exact
1. Power reducing formulas can be used to rewrite 8sin^2 xcos^2 x as 1-cos4x. True or False?
2. Find the exact value of cos15
Angle x is a third quadrant angle such that cos x = -(2/3).
What is the exact value of cos (x/2) ? Solve in simplest radical
Find the exact value. Without using a calculator
a) cos (-17pi/6) b) sec (3pi/2)
1)Find the exact value of cos 105 by using a half-angle formula.
A)sqrt 2 - sqrt 3 /2 B)-sqrt 2 - sqrt 3 /2 C)-sqrt 2 + sqrt 3 /2
Find measures of positive and negative angles that are coterminal with the given angle->8π/5
A)14π/3;-2π/3 B)2π/3;-14π/3
Use a half-angle formula to find the exact value of cos 5ð/12
Determine exact value of cos(cos^-1(19 pi)).
is this the cos (a+b)= cos a cos b- sina sin b? or is it something different. When