Current location - Training Enrollment Network - Mathematics courses - Ask for advice on math problems in junior one.
Ask for advice on math problems in junior one.
1, using the complete square formula (a+b) 2 = a 2+2ab+b 2. (a-b) 2 = a 2-2ab+b 2。

(a+b)2-(a-b)2 = a2+B2+2ab-(a2+B2-2ab)= 4ab。 Bring 7 and 4 into ab=4\3.

Similarly, (a+b) 2+(a-b) 2 = 2a 2+2b 2. The solution is a 2+b 2 = 1 1 \ 2.

2, or use the complete square formula, (a+b) 2 = a 2+b 2+2ab = 5+4 = 9.

(a-b)^2=a^2+b^2-2ab=5-4= 1

(2 stands for square, \ stands for division, which is also a fractional line, and \ is preceded by numerator)

Typing on the ipad is not easy. Some of them are abbreviated. Please forgive me. Give me the best. Are you fully prepared to save your first year of school life after completing the task? Super-class, right?