How do you find the exact value of cos54? - Socratic
Jun 24, 2016 · How do you find the exact value of #cos54#? Trigonometry Trigonometric Identities and Equations Half-Angle Identities. 1 Answer
Double Angle Identities - Trigonometry - Socratic
How do you express cos(4θ) in terms of cos(2θ) using the double angle identity? If Cosx = 5/13 and x is reflex, how do you find the exact value of cos2x? How do you find the exact value of cos2x, given that cotx = -5/3 with pi/2<x<pi?
What is #tan(45)#, #sin(45)# and #cos(45)#? - Socratic
Nov 17, 2017 · tan(45^@)=1 sin(45^@)=sqrt2/2 cos(45^@)=sqrt2/2 45^@ is a special angle, along with 30^@, 60^@, 90^@, 180^@, 270^@, 360^@. tan(45^@)=1 sin(45^@)=sqrt2/2 cos(45 ...
How do you evaluate \frac { \sin ^ { 2} 15^ { \circ } + \sin 75 ...
May 6, 2018 · (sqrt6/4)(sqrt(2 - sqrt3)) f(x) = N/D = (sin^2 15 + sin 75)/(cos^2 36 + cos^2 54) First, evaluate the denominator D. Since, cos (54) = cos (90 - 54) = sin 36 cos^2 54 = sin^2 36 --> Therefor: D = cos^2 36 + sin^2 36 = 1 Next, evaluate the numerator N. Since sin 75 = cos (90 - 75) = cos 15. Therefor,--> N = sin 15(sin 15 + cos 15) = sin 15(sqrt2cos (15 - 45)) N = sin …
Amplitude, Period and Frequency - Trigonometry - Socratic
Frequency and period are related inversely. A period #P# is related to the frequency #f# # P = 1/f#. Something that repeats once per second has a period of 1 s.
Let z=3 (cos (15°)+isin (15°)), W= 5 (cos (54°+isin (54 ... - Socratic
Feb 20, 2018 · Let z=3(cos(15°)+isin(15°)), W= 5(cos(54°+isin(54°)). Then zw can be expressed as r(cosα°+isinβ°),where r is a real number,0≤α≤90 and 0≤β≤90.what is r+α+β?
Proving Identities - Trigonometry - Socratic
The best videos and questions to learn about Proving Identities. Get smarter on Socratic.
How do you find the exact values of cos 15 using the half
Aug 30, 2015 · color(red)(cos15 = sqrt(2 +sqrt3)/2) > The cosine half-angle formula is cos(x/2) = ±sqrt((1 + cos x) / 2) The sign is positive if x/2 is in the first or fourth quadrant and negative if x/2 is in the second or third quadrant. 15° is in the first quadrant, so the sign is positive. 15= 30/2 ∴ cos15 = cos(30/2) = sqrt((1+cos30)/2) cos15 = sqrt((1 + sqrt3/2)/2) = sqrt((2 + sqrt3)/4) cos15 ...
Solving Trigonometric Equations - Trigonometry - Socratic
Solution. Use trig identity to transform (cos x + cos 3x): F(x) = 2cos 2x.cos x + cos 2x = cos 2x(2cos x + 1 ) = 0. Next, solve the 2 basic trig equations. 2. Transform a trig equation F(x) that has many trig functions as variable, into a equation that has only one variable. The common variables to be chosen are: cos x, sin x, tan x, and tan (x/2)
How do you multiply \sin ( - \frac { 50\pi } { 3} ) \cdot \cos \frac ...
Mar 2, 2018 · First, simplify the 2 factors --> #sin ((- 50pi)/3) = sin (- (2pi)/3 - (48pi)/3) = sin ((- 2pi)/3 - 16pi) =# ...