We know that:
There is also an interesting property that relates the sine and the cosine of an angle:
We can find the cosine of theta using this equation:
![\begin{gathered} \cos ^2(\theta_1)=1-\sin ^2(\theta_1) \\ \cos (\theta_1)=\sqrt{1-\sin^2(\theta_1)} \\ \cos (\theta_1)=\sqrt[]{1-(-\frac{12}{13})^2} \\ \lvert\cos (\theta_1)\rvert=\sqrt[]{1-\frac{144}{169}}=\sqrt[]{\frac{25}{169}} \\ \lvert\cos (\theta_1)\rvert=\frac{5}{13} \end{gathered}](https://tex.z-dn.net/?f=%5Cbegin%7Bgathered%7D%20%5Ccos%20%5E2%28%5Ctheta_1%29%3D1-%5Csin%20%5E2%28%5Ctheta_1%29%20%5C%5C%20%5Ccos%20%28%5Ctheta_1%29%3D%5Csqrt%7B1-%5Csin%5E2%28%5Ctheta_1%29%7D%20%5C%5C%20%5Ccos%20%28%5Ctheta_1%29%3D%5Csqrt%5B%5D%7B1-%28-%5Cfrac%7B12%7D%7B13%7D%29%5E2%7D%20%5C%5C%20%5Clvert%5Ccos%20%28%5Ctheta_1%29%5Crvert%3D%5Csqrt%5B%5D%7B1-%5Cfrac%7B144%7D%7B169%7D%7D%3D%5Csqrt%5B%5D%7B%5Cfrac%7B25%7D%7B169%7D%7D%20%5C%5C%20%5Clvert%5Ccos%20%28%5Ctheta_1%29%5Crvert%3D%5Cfrac%7B5%7D%7B13%7D%20%5Cend%7Bgathered%7D)
Since theta is in the third quadrant then its cosine must be a negative number so:
Step-by-step explanation:
z°=180°-25°
z°= 155°
z°=x°=155° (vertically opposite angle).
w°=25°(alternate angle).
y°=z°=155°(alternate angle).
hope this helps you.
Odd numbers are of the from a(n)=a+d(n-1) where a=1 and d=2 so
a(n)=1+2(n-1)=2n-1 and we need the number of odds in the range 1 to 38
2n-1≤38
2n≤39
n≤19.5, so there are 19 odd numbers in [1,38]
And since Julie bet on two even numbers as well, the probability of getting an odd number or the two evens she picked is:
(19+2)/38
21/38
