This particular question speaks volumes, and your response will determine wether it's a logical approach or not, because when it comes to Bitcoin investment, it's best to invest with an amount you aren't needing anytime soon, like in five to ten years time from now, , Because the way Bitcoin is structured, it's more beneficial to invest and hold for a very long period of time than to invest and be hoping on cashing out big in just a year time, because due to how uncertain life is, Bitcoin can retrace back to a lower figure, far bellow what you bought it, and due to the fact that you need the money urgently, it might result in you selling at a loss, so it's very important to invest money you aren't needing back anytime soon, so as not to sell when you ought not to.
Then lastly, how small is the interest? Because the size of the interest will determine wether it's a logical thing to do or not, but overall, I really don't like the idea of borrowing money to invest, because it puts you under unnecessary pressure that isn't ideal for a Bitcoin investor.