Simply you can substitute theta=45 degrees (or any angle,not zero) in left hand side and right hand side.
or 
using a^2 - b^2 =(a+b)(a-b)
= sin(2x+x)sin(2x-x)
= sin 3x sin x
        
             
        
        
        
Answer:
   (d)  f(x) = -x²
Step-by-step explanation:
For the vertex of the quadratic function to be at the origin, both the x-term and the constant must be zero. That is, the function must be of the form ...
   f(x) = a(x -h)² +k . . . . . . . . . . vertex form; vertex at (h, k)
   f(x) = a(x -0)² +0 = ax² . . . . . vertex at the origin, (h, k) = (0, 0)
Of the offered answer choices, the only one with a vertex at the origin is ...
   f(x) = -x² . . . . . a=-1
 
        
             
        
        
        
Answer:
56
Step-by-step explanation:
 
        
                    
             
        
        
        
Total number of animals at the shelter = 15 + 12 +3 + 5 = 35 animals.
Let the total number of animals be represented by 100%
There are 15 dogs and 12 cats so:
% Number of dogs  = 15/35 x 100% = 42.86%
% Number of cats  = 12/35 x 100%  =  34.28%