Ill write A for alpha and B for beta.
AB = c/a and A + B = -b/a
A^4 + B^4 = (A^2 + B^2)^2 - 2A^2B^2
= [(A + B)^2 - 2AB] ^2 - 2A^2B^2
Plugging in the values for A+B and AB we get
A^4 + B^4 = [(-b/a)^2 - 2c/a]^2 - 2(c/a)^2
= (b^2 / a^2 - 2c / a)^2 - 2c^2/a^2
= (b^2 - 2ac)^2 - 2c^2
---------------- -----
a^4 a^2
= (b^2 - 2ac)^2 - 2a^2c^2
-----------------------------
a^4
Answer:
answer is 1, 4, 5 (just took the test, those are the answers)
Step-by-step explanation:
Answer:
4, 6, 4
6, 12, 8
8, 12, 6
Step-by-step explanation:
Tetrahedron:
4 faces, 6 edges, 4 vertices
Cube:
6 faces, 12 edges, 8 vertices
Octahedron:
8 faces, 12 edges, 6 vertices
you can also use the v - e + f = 2 to check
The correct question is
Use the given information to find the exact value of the expression. sin α = 21/29, α lies in quadrant II, and cos β = 15/17, β lies in quadrant I Find sin (α - β).
we know that
sin(α − β<span>) = </span>sin α cos β − cos α sin β
α lies in quadrant II
so
cos α is negative
sin α is positive
β lies in quadrant I
so
cos β is positive
sin β is positive
step 1
find sin β
cos β=15/17
sin² β+cos² β=1-----------> sin² β=1-cos² β----> sin² β=1-(15/17)²
sin² β=1-225/289-----> 64/289
sin β=8/17
step 2
find cos α
sin α = 21/29
cos² α + sin² α=1----> cos² α=1-sin² α---> cos² α=1-(21/29)²---> 1-441/841
cos² α=400/841------> cos α=-20/29 (remember cos α is negative)
step 3
find sin(α − β)
sin α = 21/29 cos α=-20/29
sin β=8/17 cos β=15/17
sin(α − β) = [21/29]*[15/17] − [-20/29*]*[8/17]
sin(α − β) = [315/493] − [-160/493]
sin(α − β) = 475/493
the answer is
sin(α − β) = 475/493
The answer is 4p=c because p is for people and person (they both mean the same thing)
