What does it mean to have real roots?

Question 1: What does it mean to have real roots? What does it mean to have a solution?

Question 2: What does it mean to have only one real root? Answer: It means that when the quadratic equation of one variable ax2+bx When the discriminant Δ=b2-4ac=0 of +c=0, the equation has two identical real roots, which can also be said to be only one real root.

Question 3: What does the "Beware of Bears" stickers often posted on cars now mean? 5 points "Beware of Bears" is a warning to remind people to pay attention to bears in Hokkaido, Japan. Posting it on the car is nothing more than telling others that the car owner is more powerful, be careful and stay away from the car. But now there are too many posts and there is nothing new.

The original meaning of "Beware of Bears" is this: There are two iconic animals in Hokkaido, one is the owl, and the other is the bear. You can always see these two in shops at tourist spots and resorts. In the past, there were probably enough bears in Hokkaido, so people posted "Beware of Bears" warning signs in places where bears frequented. Now, this warning slogan has become a trademark, with black characters on a yellow background, and is used on T-shirts, wine glasses and many other products, becoming a characteristic of Hokkaido.

Nowadays...many people are not clear about this and have become a typical example of Hari. Thinking of the last time a pure girl showed off in a T-shirt that said "no underwear", here is my sincere suggestion: don't use English words that you don't understand. Wear; don’t use signs whose origins you don’t know!!!