Verified answer

p(c) = (c + 9/c)(9c + 1/c)

p(1/c) = вместо с подставляем 1/c = (1/c + 9/(1/c))(9*(1/c) + 1/(1/c)) = (1/c + 9c)(9/c + c)

p(c)/p(1/c) = (c + 9/c)(9c + 1/c) : (1/c + 9c)(9/c + c) = 1