With some simplification,
cos⁻¹(x) - 5 cos⁻¹(x) - π/3 = 2π/3
becomes
-4 cos⁻¹(x) = π
or
cos⁻¹(x) = -π/4
However, the inverse cosine function has a range of 0 ≤ cos⁻¹(x) ≤ π, so there are no solutions to this equation.
The completed factor is (7x+2) (x+5)
Answer:
Question 11.1
At 7 : 00 pm in Sydney, it will be 10 : 00 pm in Berlin.
Question 11.2
Place | Time
Sydney | 5 : 00 pm
Berlin | 8 : 00 pm
It would be a good time for Mark and Hans to cha,t when it's 5 : 00 pm in Sydney and 8 : 00 pm in Berlin.
hope that helps ...