Answer:
im confussed
Step-by-step explanation:
Answer:
$9$
Step-by-step explanation:
Given: Thea enters a positive integer into her calculator, then squares it, then presses the $\textcolor{blue}{\bf\circledast}$ key, then squares the result, then presses the $\textcolor{blue}{\bf\circledast}$ key again such that the calculator displays final number as $243$.
To find: number that Thea originally entered
Solution:
The final number is $243$.
As previously the $\textcolor{blue}{\bf\circledast}$ key was pressed,
the number before $243$ must be $324$.
As previously the number was squared, so the number before $324$ must be $18$.
As previously the $\textcolor{blue}{\bf\circledast}$ key was pressed,
the number before $18$ must be $81$
As previously the number was squared, so the number before $81$ must be $9$.
Answer:
+120/169 or -120/169
Step-by-step explanation:
- let
![cos^{-1}[\frac{5}{13} ] = \alpha](https://tex.z-dn.net/?f=cos%5E%7B-1%7D%5B%5Cfrac%7B5%7D%7B13%7D%20%20%5D%20%3D%20%5Calpha)
where, alpha is some angle that satisfies the assumed condition.
- so,

[ taking cos to the other side or applying cos on both sides]
- now, substitute this in the given expression
as sin
= 
[by general trigonometry formula:
]
so if
, we can get sin
from the above formula as + or - 12/13
(because, after taking square root on both sides we keep + or -]
- as, sin
![2\beta = 2*sin[\beta ]*cos[\beta ]](https://tex.z-dn.net/?f=2%5Cbeta%20%20%3D%202%2Asin%5B%5Cbeta%20%5D%2Acos%5B%5Cbeta%20%5D)
[by general trigonometry formula]
- here, now
![sin[2\alpha ]=2*(+or- 12/13)*5/13\\](https://tex.z-dn.net/?f=sin%5B2%5Calpha%20%5D%3D2%2A%28%2Bor-%2012%2F13%29%2A5%2F13%5C%5C)
so, the final value can be 120/169 or -120/169.
Maybe you should work on starting you're sentences.