1.1. 9а^3/6b^2 * 4b^3/3a^4=3/3 * 2b/a=2b/a
1.2. 2a-1/a-3 * 1/3= 2a-1/3(a-3)
1.3. 1/c * cy+c^2-cy/y=1/c * c^2/y=c/y
3.1. -25+24=-1
3.2. √0,81/9 -1=9/10*9 -1= 1/10 -1= 1-10/10=- 9/10
3.3. 9-7,5=1,5
4.1. x^2=12
x=-2√3
x=2√3
4.2. x^2=-11
x=√-11
x=-√-11
4.3. x^2=64
x=8
x=-8