So the problems ask to find and calculate the exact value of the trigonometric equation in the following equations and the best answers would be the following:
#1. sqrt(3)/3
#2. Arcsine of zero is 0
#3. x/sqrt(4-x^2)
I hope you are satisfied with my answer and feel free to ask for more if you have questions and further clarifications. Have a nice day
-x^2 - 2x - 5=0
-(x^2 + 2x + 1) -4=0
(x +1)^2= -4
=> Impossible. There is no x
Answer: 
Step-by-step explanation:

Answer:
P(A or B) is 0.72
Step-by-step explanation:
Given : P(A) = 0.3 and P(B) = 0.6
To Find:P(A or B) = P(A∪B)
Solution :
We are given that A and B are two independent events
Property : If A and B are independent events then 
So, 


Formula : 


Hence P(A or B) is 0.72
75:3 is equivalent to 25:1 or just 25