Answer: 28 decibels.
Step-by-step explanation:
1. To solve this exercise you must observe the graph attached in the problem, where the intensity of the sound is represented in the x-axis and the decibel measure is represented in the y-axis.
2. As you can see in the graph, when the value of x is 500 (x=500) the value of y is 28 (y=28).
3. Therefore, the answer is the second option: 28 decibels.
Answer:
x=-7
Step-by-step explanation:
so if you multiply two negative numbers you get a positive and and -7 * -3 is just doing 3*7 which is 21 and that is the answer to -3*-7 and 21 minus 5 is 16 so there´s that and hope this helps
Trig was never my strong point but ok
remember the quotient rule
![\frac{dy}{dx} \frac{f(x)}{g(x)}=\frac{f'(x)g(x)-g'(x)f(x)}{(g(x))^2}](https://tex.z-dn.net/?f=%5Cfrac%7Bdy%7D%7Bdx%7D%20%5Cfrac%7Bf%28x%29%7D%7Bg%28x%29%7D%3D%5Cfrac%7Bf%27%28x%29g%28x%29-g%27%28x%29f%28x%29%7D%7B%28g%28x%29%29%5E2%7D)
so
remember the pythagorean identity sin²(x)+cos²(x)=1
so
![\frac{dy}{dx} \frac{1+sin(x)}{1-cos(x)}=\frac{cos(x)(1-cos(x))-sin(x)(1+sin(x))}{(1+cos(x))^2}=](https://tex.z-dn.net/?f=%5Cfrac%7Bdy%7D%7Bdx%7D%20%5Cfrac%7B1%2Bsin%28x%29%7D%7B1-cos%28x%29%7D%3D%5Cfrac%7Bcos%28x%29%281-cos%28x%29%29-sin%28x%29%281%2Bsin%28x%29%29%7D%7B%281%2Bcos%28x%29%29%5E2%7D%3D)
![\frac{cos(x)-cos^2(x)-sin(x)-sin^2(x)}{(1+cos(x))^2}=](https://tex.z-dn.net/?f=%5Cfrac%7Bcos%28x%29-cos%5E2%28x%29-sin%28x%29-sin%5E2%28x%29%7D%7B%281%2Bcos%28x%29%29%5E2%7D%3D)
![\frac{cos(x)-sin(x)-sin^2(x)-cos^2(x)}{(1+cos(x))^2}=](https://tex.z-dn.net/?f=%5Cfrac%7Bcos%28x%29-sin%28x%29-sin%5E2%28x%29-cos%5E2%28x%29%7D%7B%281%2Bcos%28x%29%29%5E2%7D%3D)
![\frac{cos(x)-sin(x)-(sin^2(x)+cos^2(x))}{(1+cos(x))^2}=](https://tex.z-dn.net/?f=%5Cfrac%7Bcos%28x%29-sin%28x%29-%28sin%5E2%28x%29%2Bcos%5E2%28x%29%29%7D%7B%281%2Bcos%28x%29%29%5E2%7D%3D)
![\frac{cos(x)-sin(x)-(1)}{(1+cos(x))^2}=](https://tex.z-dn.net/?f=%5Cfrac%7Bcos%28x%29-sin%28x%29-%281%29%7D%7B%281%2Bcos%28x%29%29%5E2%7D%3D)
![\frac{cos(x)-sin(x)-1}{(1+cos(x))^2}=](https://tex.z-dn.net/?f=%5Cfrac%7Bcos%28x%29-sin%28x%29-1%7D%7B%281%2Bcos%28x%29%29%5E2%7D%3D)
![\frac{-sin(x)+cos(x)-1}{(1+cos(x))^2}=](https://tex.z-dn.net/?f=%5Cfrac%7B-sin%28x%29%2Bcos%28x%29-1%7D%7B%281%2Bcos%28x%29%29%5E2%7D%3D)
taht is the last option
thanks to jdoe0001 for showing me which identity to use