1. 1/9a²-2/3a+1
2. 4/25x²+2/3x+25/36
3. 0.09a²-0.12a+0.04
1. 1/9a²-2/3a+1
2. 4/25x²+2/3x+25/36
3. 0.09a²-0.12a+0.04
1. 1/9a²-2/3a+1
=(1/3a)²-2×1/3a×1+1²
=(1/3a-1)²
2、4/25x²+2/3x+25/36
=(2/5x)²+2×2/5x×5/6+(5/6)²
=(2/5x+5/6)²
3、 0.09a²-0.12a+0.04
=(0.3a)²-2×0.3a×0.2+(0.2)²
=(0.3a-0.2)²
1/(9a²)-2/(3a)+1=[1/(3a)-1]²=(1-3a)²/(9a²)
4/25x²+2/3x+25/36=[2/(5x)]²+2/3x+{5/6}²=[2/(5x)+(5/6)]²=(12+25x)²/(900x²)
0.09a²-0.12a+0.04=(0.3a)²-0.12a+0.2²=(0.3a+0.2)²
1. 1/9a²-2/3a+1=(1/3a)^2-2*1/3a*1+1=(1/3a-1)^2
2. 4/25x²+2/3x+25/36=(2/5x)^2+2*2/5x*5/6+(5/6)^2=(2/5x+5/6)^2
3. 0.09a²-0.12a+0.04=(0.3a)^2-2*0.3a*0.2+0.2^2=(0.3a-0.2)^2
1. 1/9a²-2/3a+1
=(1/3a-1)^2
2. 4/25x²+2/3x+25/36
=(2/5x+5/6)^2
3. 0.09a²-0.12a+0.04
=(0.3a-0.2)^2