Question: 2csc^2x=4 I need to find the solution set, 0 to 360, and the problem is I get to
2csc^2x=4
csc^2x=2
and I don't know what to do from here, can you also tell me if my steps are correct. thank you.
2csc^2x=4
csc^2x=2
and I don't know what to do from here, can you also tell me if my steps are correct. thank you.
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Hello,
Yes you are right at the beginning
Csc²(x) = 2
Then
Csc(x) = +√2 or -√2
What is Csc ? it is the inverse of sine
1/sin(x) = +√2 or -√2
sin(x) = 1/√2 or -1/√2
Your calculator or your memory will tell you that
Arcsin (1/√2) = 45°
The trigonometric circle shows you that 180° - 45° = 135° has the same sine (check on calculator)
Arcsin (-1/√2) = - 45° = 360 - 45 = 315°
The trigonometric circle shows you that 180° - (-45°) = 225° has the same sine (check on calc.)
Then the set of solutions is { 45° ; 135° ; 225° ; 315° }
Hope it helped !
Bye !
Yes you are right at the beginning
Csc²(x) = 2
Then
Csc(x) = +√2 or -√2
What is Csc ? it is the inverse of sine
1/sin(x) = +√2 or -√2
sin(x) = 1/√2 or -1/√2
Your calculator or your memory will tell you that
Arcsin (1/√2) = 45°
The trigonometric circle shows you that 180° - 45° = 135° has the same sine (check on calculator)
Arcsin (-1/√2) = - 45° = 360 - 45 = 315°
The trigonometric circle shows you that 180° - (-45°) = 225° has the same sine (check on calc.)
Then the set of solutions is { 45° ; 135° ; 225° ; 315° }
Hope it helped !
Bye !
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yeah, you're correct so far....but what you should do,
cosec(x)=2
Remember cosec(x)= 1/sin(x),
is the same as {cosec(x)}^2= (1/sin(x)}^2
1/ sin^2(x)=2
cross multiply to get
1=2sin^2 (x)
1/2= sin^2(x)
Sin(x) = √(1/2)(a calculator would help here,haha)
it will be, (x)= sin (+√o.5 or -√0.5)
(you will get 2 values for +√o.5 and -√0.5 each because it will be where sin has positive and negative angles)(positive lies in 0-90 and 90-180, where as negative lies in 180-270 and 270-360 degrees)
just subtract your angles in positive region to 270 and 360
x= 45° ; 135° ; 225° ; 315°
Hope this helped...........did it a while aback
cosec(x)=2
Remember cosec(x)= 1/sin(x),
is the same as {cosec(x)}^2= (1/sin(x)}^2
1/ sin^2(x)=2
cross multiply to get
1=2sin^2 (x)
1/2= sin^2(x)
Sin(x) = √(1/2)(a calculator would help here,haha)
it will be, (x)= sin (+√o.5 or -√0.5)
(you will get 2 values for +√o.5 and -√0.5 each because it will be where sin has positive and negative angles)(positive lies in 0-90 and 90-180, where as negative lies in 180-270 and 270-360 degrees)
just subtract your angles in positive region to 270 and 360
x= 45° ; 135° ; 225° ; 315°
Hope this helped...........did it a while aback
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I csc^2 x = 2, then sin^2 x = 1/2 and sin x = ± 1/√2, which means that x = 30°, 150°, 210° or 330°.
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x = 45 || x = 135 || x = 225 || x = 315