If sec theta= 10/9 FIND:
csc theta=__________
sin theta=___________
cos theta=___________
tan theta=___________
cot theta=___________
*****NO DECIMALS******
csc theta=__________
sin theta=___________
cos theta=___________
tan theta=___________
cot theta=___________
*****NO DECIMALS******
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For starters, there's a big different between Sec(10/9) and Sec(theta)= 10/9
The first one means that 10/9 is an angle.
The second means that the Sec calculation OF the angle theta = 10/9.
Anywhoo...
If sec(theta) = 10/9
Then simply use your identities:
Cos(x) = 1/Sec(x)
Sin(x) = 1/Csc(x)
Tan(x) = 1/Cot(x)
So if:
Sec(x) = 10/9
then:
Cos(x) = 9/10
Now we need to get it in terms of Sin(x) to finish the rest of the problems.
Recall the identity: Cos^2(x) + Sin^2(x) = 1
so that means:
Sin(x) = Sqrt(1-Cos^2(x))
Plug in our value for Cos(x):
Sin(x) = Sqrt(1-[(9/10)^2])
invert to find Csc(x):
1/{Sqrt(1-[(9/10)^2])}
and Tan(x) = Sin/Cos so:
(10/9)*Sqrt(1-[(9/10)^2])
and inverting Tan(x) gives us Cot(x):
9/{10*Sqrt(1-[(9/10)^2])}
The first one means that 10/9 is an angle.
The second means that the Sec calculation OF the angle theta = 10/9.
Anywhoo...
If sec(theta) = 10/9
Then simply use your identities:
Cos(x) = 1/Sec(x)
Sin(x) = 1/Csc(x)
Tan(x) = 1/Cot(x)
So if:
Sec(x) = 10/9
then:
Cos(x) = 9/10
Now we need to get it in terms of Sin(x) to finish the rest of the problems.
Recall the identity: Cos^2(x) + Sin^2(x) = 1
so that means:
Sin(x) = Sqrt(1-Cos^2(x))
Plug in our value for Cos(x):
Sin(x) = Sqrt(1-[(9/10)^2])
invert to find Csc(x):
1/{Sqrt(1-[(9/10)^2])}
and Tan(x) = Sin/Cos so:
(10/9)*Sqrt(1-[(9/10)^2])
and inverting Tan(x) gives us Cot(x):
9/{10*Sqrt(1-[(9/10)^2])}