If the square + 1 of the algebraic formula 4 * a plus a monomial form can form a complete square, then; [1] write all possible monomials in line with the meaning of the problem; [2] write all corresponding complete square forms

If the square + 1 of the algebraic formula 4 * a plus a monomial form can form a complete square, then; [1] write all possible monomials in line with the meaning of the problem; [2] write all corresponding complete square forms

1.+4a,-4a
2.(2a+1)(2a+1),(2a-1)(2a-1)
It seems that there are only two. Think about it again
Yes, and the fourth power of 4 * a
The square of (2a * a + 1)

Mathematics in grade one, please answer in detail, thank you! (2219:5:32)
Find the reciprocal of the following numbers and connect them with ＜:
- 5 / 12 & # 160; - # 160; 3.7 & # 160; - # 160; - - 1.8

-1.8 ＜ - 5 / 12 ＜ 1 / 6 ＜ 2 ＜ 3.7
Reciprocal: - 12 / 5,1 / 3.7,6,1 / 2, - 1 / 1.8
-12/5＜-1/1.8＜1/3.7＜1/2＜6