Find cot θ if csc θ = negative square root of thirty seven divided by six divided by six and tan θ > 0.
@IMStuck
@IMStuck
I'm here! Let me take a look!
\[\csc \theta=\frac{ \frac{ -\sqrt{37} }{ 6 } }{ 6 }\]?
No, its \[\csc \theta=-\frac{ \sqrt{37} }{ 6 }\]
Oh that is so much better! NOW let me look... ; )
The first thing I did was to convert the csc to sin. Do you know the relationship between csc and sin?
csc=1/sin
That's right, so to find the sin of the given angle, just flip the fraction. If \[\csc \theta=-\frac{ \sqrt{37} }{ 6 }\]then \[\sin \theta=-\frac{ 6 }{ \sqrt{37} }\]Now that that's out of the way...
The second thing we need to deal with is the fact that they told you that the tangent is > 0, meaning it is positive. Do you know what tangent is in terms of sin and cos?
tan=sin/cos
Cool. Now where is tangent positive? Which 2 quadrants? There are 2.
1 and 3
Good good....BUT
they tell you that the sin of the angle is -6/sqrt 37. So it has to be in the quadrant in which sin (the y value) is negative. In which quadrant is the sin negative...I or III?
3
Still with me? We're about done! Keep up the good hard work! This isn't easy stuff at all!!!
You're right QIII. So here's a pic so far:
|dw:1403645872237:dw|We need to find x. How do we do that?
sqrt(37)^2--6^2=b^2
good.....
37-36=b^2 1=b^2 1=b
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Ok...NEXT is to convert cotangent into sin and cos. What is that identity?
cot theta = ???
cot=cos/sin
Wow! You really know your stuff! Good job! Ok, if cot= cos/sin, we need to find that using the values of the triangle we drew.
what are cos and sin?
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