171k views
3 votes
40 points!!!!!PLEASE HELP!!!!

40 points!!!!!PLEASE HELP!!!!-example-1

2 Answers

5 votes

Answer:

This is the square root of 26 over 26. The second 26 is not inside the square root. You can type it in as sqrt(26)/26.

Explanation:

User Samsul Islam
by
5.2k points
4 votes

Answer:
(√(26))/(26)

This is the square root of 26 over 26. The second 26 is not inside the square root. You can type it in as sqrt(26)/26.

========================================================


\theta is in Q1 so
\sin(\theta) > 0

Use the trig identity below and plug in the given value to get...


\sin\left((x)/(2)\right) = \pm \sqrt{(1-\cos(x))/(2)}\\\\\sin\left((2\theta)/(2)\right) = \pm \sqrt{(1-\cos(2\theta))/(2)}\\\\\sin(\theta) = \sqrt{(1-\cos(2\theta))/(2)} \ \ \text{since } \ \sin(\theta) > 0\\\\\sin(\theta) = \sqrt{(1-(12)/(13))/(2)}\\\\


\sin(\theta) = \sqrt{(1)/(26)}\\\\\sin(\theta) = (√(1))/(√(26))\\\\\sin(\theta) = (1)/(√(26))\\\\\sin(\theta) = (1*√(26))/(√(26)*√(26)) \ \ \text{ rationalizing denominator}\\\\\sin(\theta) = (√(26))/(26)\\\\

------------------------------

Edit:

To find cos(theta), we use the pythagorean identity below


\sin^2(\theta) + \cos^2(\theta) = 1\\\\\cos^2(\theta) = 1-\sin^2(\theta)\\\\\cos(\theta) = √(1-\sin^2(\theta))\ \ \text{cosine is positive in Q1}\\\\\cos(\theta) = \sqrt{1-\left((1)/(√(26))\right)^2}\\\\\cos(\theta) = \sqrt{1-(1)/(26)}\\\\\cos(\theta) = \sqrt{(25)/(26)}\\\\\cos(\theta) = (√(25))/(√(26))\\\\\cos(\theta) = (5)/(√(26))\\\\\cos(\theta) = (5√(26))/(√(26)*√(26))\\\\\cos(\theta) = (5√(26))/(26)\\\\

User ImJames
by
5.0k points