Question

Please explain I am confused thank you

Answer 1

Answer:

Answer A researcher wants to compare the means of four different groups. Procedure is shown below:- Solution- 1stly Checking that if you have normal distribution or not normal distribution. To know thview the full answer

Answer 2

Answer:

Step-by-step explanation:

You have to use the half angle identities for trig.  You will also need access to a unit circle with radian measures of angles.  The identity for the half angle for sin is

$sin(\frac{\theta}{2})=$±$\sqrt{\frac{1-cos\theta}{2} }$

To use a half angle identity, the trick is to rewrite the half angle so that when you bring up that 2 in the denominator and flip it to multiply you get back the angle you started with.  Our angle is 7π/8.  Divide the 8 by 2 and you get your angle to be in the form $sin(\frac{\frac{7\pi}{4} }{2})$

Note that when you bring up the 2 and flip it to multiply you get back 7π/8.

Do you see that?  For the formula, then, our angle theta is 7π/4.  If you look to the unit circle, you see that the cosine of that angle is √2/2.  Filling in the formula:

$sin(\frac{\frac{7\pi}{4} }{2})=+/-\sqrt{\frac{1-\frac{\sqrt{2} }{2} }{2} }$

Get a common denominator up on top there and simplify:

$+/-\sqrt{\frac{\frac{2-\sqrt{2} }{2} }{2}$

You'll bring up that bottom 2 and flip it to multiply:

$+/-\sqrt{\frac{2-\sqrt{2} }{2}*\frac{1}{2} }$

Simplify to get

$+/-\sqrt{\frac{2-\sqrt{2} }{4} }$

Since 4 is a perfect square, the final simplification will be to pull it out as a 2:

$sin(\frac{7\pi}{8})=$±$\frac{\sqrt{2-\sqrt{2} } }{2}$

And you're all done!  Easy if you know how to use the formula and the unit circle.