SOLUTION: Suppose sin x = 1/7
cos x > 0, sin y = −2/5
and cos y < 0. Then
cos x =
cos y =
Find each of the following quantities:
sin(x + y) =
cos(x + y) =
tan(x + y) =
Algebra.Com
Question 923637: Suppose sin x = 1/7
cos x > 0, sin y = −2/5
and cos y < 0. Then
cos x =
cos y =
Find each of the following quantities:
sin(x + y) =
cos(x + y) =
tan(x + y) =
Answer by stanbon(75887) (Show Source): You can put this solution on YOUR website!
Suppose sin x = 1/7 cos x > 0,
Note: cos(x) = sqrt(49-1)/7 = sqrt(48)/7
-----------------------------------------------
sin y = −2/5 and cos y < 0.
Note: cos(y) = -sqrt(25-4)/5 = -sqrt(21)/5
------------------------------
Then
cos x = 4sqrt(3)/7
cos y = -sqrt(21)/5
----------------------------
Find each of the following quantities:
sin(x + y) = sin(x)cos(y)+cos(x)sin(y)
Substitute to get the numerical answer.
-----
cos(x + y) = cos(x)cos(y)-sin(x)sin(y)
Substitute::
tan(x + y) =
Divide sin(x+y) by cos(x+y)
==================================
Cheers,
Stan H.
===============
RELATED QUESTIONS
Suppose sin x = 5/7
cos x > 0, sin y = − 1/5
and cos y < 0. Then
cos x =
cos... (answered by lwsshak3)
Suppose sin x =2/7,cos x > 0, sin y = − 2/5 and cos y < 0. Then
cos x=
cos y=
Find (answered by CPhill)
Suppose sin x = 1/7
cos x > 0, sin y = −2/5
and cos y < 0. Then
cos x =
cos y (answered by ewatrrr)
Suppose sin x = 1/7
cos x > 0, sin y = −2/5
and cos y < 0. Then
cos x =... (answered by lwsshak3)
Verify the identity.
(cos(x) - cos(y))/(sin(x) + sin(y)) + (sin(x) - sin(y))/(cos(x) + (answered by solver91311)
Evaluate:
sin(x + y) if sin x =3/5, sec x > 0, cos y = − 2√(5)/5, and tan... (answered by ewatrrr,lwsshak3)
How do I evaluate these this two sine and cosine problems. Difficult!?
Evaluate cos(a... (answered by richard1234)
How do I evaluate these this two sine and cosine problems. Difficult!?
Evaluate cos(a... (answered by stanbon)
Suppose sin x= 2/7, sin y= -1/5, cos x= 3 √5/7, cos y= -2 √6/ 5
Find sin(x+y),... (answered by Alan3354,MathLover1)