-1/2 ab 100x squared y squared -x/8 2πR

A+b x square -y square a square -2a+ 1

Question 2-1/2 3 3 4

The third question -x cubic x quadratic -2x 1

The fourth (a+ 1) square

For example, in the fifth proposal, each book is A yuan, each pen is B yuan, and it costs (4a+5b) yuan to buy four books and five pens.

4n/2-a

Rule a (a+2 )+ 1=(a+ 1) quadratic.

A little taxi, hope to adopt.

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