1. The problem statement, all variables and given/known data If a clock in an airplane is found to slow down by 5 parts in 1013, (i.e. Δt/Δto = 1 + 5x10-13), at what speed is the airplane travelling? (Hint: You may need to use the binomial expansion for γ.) To be honest, I'm really confused about what this question's telling me. What's in the brackets? 2. Relevant equations γ = 1/√(1-v2/c2) That's the equation I used. 3. The attempt at a solution When I rearranged the equation to find the velocity, I got v = √((1-(1/γ)2)(c2)) I subbed in 1 + 1.5x10-13 for γ but I keep getting 0 as my velocity and the answer's supposed to be 300 m/s. Am I even doing this right? Thanks in advance! I appreciate any help you can give me!