1) (а-4b)²-8ab-17b=(a²-2•a•4b+4b²)-8ab-17b=a²-8ab+4b²-8ab-17b=a²+4b²-17b
2)-9c²+(3c+b)²-b²=-9c²+(9c²+2•3c•b+b²)-b²=-9c²+9c²+6bc+b²-b²=6bc
3) (5a-6)²-(5a-6)(5a+6)=(5a-6)²-(5a-6)²=0
1) 2,5 * 16 - 14 = 40 - 14 = 26
2) 1. = x^12 2. x^2 3. x^35 4. x^4
3) -20m^7n^2 2. -3^4m^28n^8
4) 3x^2-3x+3
5) 1. 27^3 2. не знаю
Только 5
1)lg√(30/3)=lg√10=1/2
2)-2+4=2
3)log(0,75)4/3=-1
<span>3(x-2y)-2(3x-y) = 0
3*x - 3*2y -2*3x-2*(-y) = 0
3x - 6y - 6x + 2y = 0
-3x - 4y = 0
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