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the given point p is located on the unit circle State the quadrant and find the angle also sin,cos,tan

the given point p is located on the unit circle State the quadrant and find the angle also sincostan class=

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Question 2


Note: Let t = theta since I there is no theta symbol on my keyboard.


(0, -1) = (cos t, sin t)


cos t = 0


sin t = -1


I read the answer from the given point.


On the unit circle, the point (0, -1) lies at 3pi/2. So, angle theta is 3pi/2.


tan t = sin t/cos t


tan t = cos t ÷ sin t


Therefore, tan t = what?


You finish....


Answer with explanation:

We know that any point located at (x,y)

Also, if the x-value and y-value both are positive then the point lie in first quadrant.

if both are negative then it lie in third quadrant.

If x-value is positive and y-value is negative then it lie in the fourth quadrant.

If x-value is negative and y-value is positive then it lie in the second quadrant.

The [tex]\sin \theta=\dfrac{y}{\sqrt{x^2+y^2}}[/tex]

[tex]\cos \theta=\dfrac{x}{\sqrt{x^2+y^2}}[/tex]

and [tex]\tan \theta=\dfrac{y}{x}[/tex]

1)

 [tex]P(-\dfrac{1}{2},\dfrac{\sqrt{3}}{2})[/tex]

as x-value is negative and y-value is positive.

Hence, the point lie in the second quadrant.

Also,

[tex]x=-\dfrac{1}{2}\ ,\ y=\dfrac{\sqrt{3}}{2}[/tex]

Hence,

[tex]\sqrt{x^2+y^2}=\sqrt{(\dfrac{-1}{2})^2+(\dfrac{\sqrt{3}}{2})^2}\\\\\\\sqrt{x^2+y^2}=\sqrt{\dfrac{1}{4}+\dfrac{3}{4}}\\\\\\\sqrt{x^2+y^2}=1[/tex]

Hence, we have:

  • [tex]\sin \theta=\dfrac{\dfrac{\sqrt{3}}{2}}{1}\\\\\\\sin\theta=\dfrac{\sqrt{3}}{2}[/tex]
  • [tex]\cos \theta=\dfrac{-1}{2}[/tex]
  • and [tex]\tan \theta=\dfrac{\dfrac{\sqrt{3}}{2}}{\dfrac{1}{2}}\\\\\\\tan \theta=\sqrt{3}[/tex]

2)

P(0,-1)

As x-value is zero and y-value is negative.

Hence, the point lie on negative y-axis.

Also,

[tex]x=0\ ,\ y=-1[/tex]

Hence,

[tex]\sqrt{x^2+y^2}=\sqrt{(0)^2+(-1)^2}\\\\\\\sqrt{x^2+y^2}=1[/tex]

Hence, we have:

  • [tex]\sin \theta=\dfrac{-1}{1}\\\\\\\sin \theta=-1[/tex]
  • [tex]\cos \theta=\dfrac{0}{1}=0[/tex]
  • and [tex]\tan \theta=\dfrac{-1}{0}[/tex],

       Hence, we have:  tan θ= undefined

3)

[tex]P(-\dfrac{\sqrt{2}}{2},-\dfrac{\sqrt{2}}{2})[/tex]

which is same as:

       [tex]P(-\dfrac{1}{\sqrt{2}},-\dfrac{1}{\sqrt{2}})[/tex]

As both the points are negative, hence the point lie in the third quadrant.

Also,

[tex]x=\dfrac{-1}{\sqrt{2}}\ ,\ y=\dfrac{-1}{\sqrt{2}}[/tex]

Hence, we have:

[tex]\sqrt{x^2+y^2}=\sqrt{(\dfrac{-1}{\sqrt{2}})^2+(\dfrac{-1}{\sqrt{2}})^2}\\\\\\\sqrt{x^2+y^2}=\sqrt{\dfrac{1}{2}+\dfrac{1}{2}}\\\\\\\sqrt{x^2+y^2}=1[/tex]

Hence, we have:

  • [tex]\sin \theta=\dfrac{-1}{\sqrt{2}}[/tex]
  • [tex]\cos \theta=\dfrac{-1}{\sqrt{2}}[/tex]
  • [tex]\tan \theta=1[/tex]