Express M=cos3A + cos A and N = sin3A + sin A as a product form
1 answer:
You might be interested in
Answer:
The correct option is C.
Step-by-step explanation:
The given cubic equation is
According to the rational root theorem 1 and -1 are possible rational roots of all polynomial.
At x=-1, the value of function 0. Therefore (x+1) is the factor of polynomial and -1 is a real root.
Use synthetic division to find the remaining polynomial.
Using
USe zero product property and equate each factor equal to 0.
Therefore the equation have three real roots out of which the value of two roots are same.
Option C is correct.
