I don't know why in the first place you had a question of bitcoin a challenge or opportunity anyways bitcoin is an opportunity for the people to earn and use that digital currency for their profit, to pay the money in a totally anonymous way where no one would know where did it come from and where did it go. Bitcoin is a risky investment but higher the risk higher the rewards and no there are no successful people who haven't risked something.

Let me say it on a brief statement; It will only become a challenge once you fear opportunities. And it will only become an opportunity once you don't mind challenges. Challenges and opportunities are all around here in bitcoin, everywhere even on the real world, but it is up to you, how you want to make it want you really want it to be!

All I'm saying is, your success here in bitcoin doesn't depend whether it is considered as a challenge or an opportunity, but how you handle both!  

Bitcoin is an opportunity that could help people in so many ways. This is actually a blessing to many people who wanted an extra income, and even a total source of income to those who are unemployed and any status in life nowadays are eager to join bitcoin and to those who have already joined they are now enjoying the fruit of bitcoin, on the other hand there is a challenge also to the beginners, seeing to others have succeeded far in the bitcoin world. They might even think if others can do, why can’t I? Maybe that’s the challenge there, but it is more on great opportunity to everyone...

If it is achallenge then it is an opportunity too. Timing is always key in any investment. Buy or sell at the right time makes the difference between earning and losing. With loads of good and bad news on bitcoin, the price will continue to be volatile hence.

Anyway, good luck to you.

After many days I have found exactly what the answer I need is, how to use it for exactly a difficult math problem for many newbies.

Bitcoin is an opportunity that can become a challenge if the right measures are not taken by the individual involved.. One of the basic factor that determine this, is timing. For example those that invested in bitcoins early last year(2017) must be smiled to the bank when it's price rose from 5k to 20k later that year and early 2018, while those that invested very late last year will be sad right now as they witness a sudden price drop from the same 20k to around 3k.. So that's how this thing works. Experts have always warned that you shouldn't use an uncomfortably large amount of money when investing in bitcoins and that's because it's outcome is somewhat unpredictable. But if you ask me I will advice you to invest right now since the price is still low, but you should invest wisely though. 

For me is both it is challenge and opportunity because all invesment have risk it is a challenge for me, for a value of investment and big opportunity for me for value much higher value cause this is the time to gain more profit.

You don't have to buy a lot of Bitcoin. You don't need to borrow a large amount of cash. You can also buy other cryptocurrencies and spread the investment, but you have to do research before that.

It is a opportunity because it makes the life of the people easy and harmoniously by giving the things that you didn't have before.