Answer:


Step-by-step explanation:
From the question we are told that
Number of math tests n=15
standard deviation 1 
standard deviation 1 
Generally given the two tailed test the null hypothesis is given as 

Generally given the two tailed test the null hypothesis is given as 

 
        
             
        
        
        
You can make it easier by replacing x^n with another variable, factoring, then putting x^n back in the end. 
Using exponent and algebra rules, rewrite x^2n - 2x^n + 1 as 
(x^n)^2 - (2 x x^2) + 1
Then, let x^n = m.
m^2 - 2m + 1
Now factor that: (m - 1)^2
And now put x^n back: (x^n - 1)^2
        
             
        
        
        
Answer:
Step-by-step explanation:
2 csc²x-2 csc x-1=0
or 

 
        
             
        
        
        
-5f, -8c, 40f, 10c happy math..ing