How to solve the equation of complex numbers?

Question

Algebra

Please help me solve this equation, they said to solve it using the pascal triangle
formula Formula:
Equation:

Answer 1

Plug n=7, a=4 and b=x^2 into the formula. These strange brackets with n and k are the number of combinations, or the k-th number in the n-th line of pascal's triangle (counting from zero). Those. build a triangle until you get a string with 8 numbers starting with "1, 7..." - then substitute these coefficients for 4^k and x^(7-k) and that's it.