4(2x²-4x+3)-3x(5-4x)=8x²-16x+12-15x+12x²=20x²-31x+12
1) (m²-4n)²-(m²-2n)²= (m²-4n-m²+2n)(m²-4n+m²-2n)=-2n(2m²-6n)=12n²-4m²n.
a²-b²=(a-b)(a+b)
a=(m²-4n)²
b=(m²-2n)²
2) (x-2y)²+4(x-2y)+4=x²-4xy+4y²+4x-8y+4
(a-b)²=a²-2×a×b+b²
a=x
b=2y
(x-2y)²+4(x-2y)+4=((x-2y)+2)²
a²+2×a×b+b²=(a+b)²
a=(x-2y)
b²=4=>√b²=√4=>b=2
3) (m²-4n)²-(m²-2n²)=(m²)²-2×m²×4n+(4n)²-m²+2n²=m⁴-8m²n+16n²-m²+2n²=m⁴-m²-8m²n+18n²
(a-b)²=a²-2×a×b+b²
a=m²
b=4n
А) 5(7-3√х)-3(2х-5√х)=41
35-15√х-6х+15√х=41
-6х+35=41
-6х=41-35
-6х=6
-х=1
х=-1
б) 2(3-5√х)-5(х-2√х)=х
6-10√х-5х+10√х=х
6-5х=х
6=х+5х
6=6х
6х=6
х=1
Y=5x-tgx, y´=5-1/cosˇ2x, y´(pí/4)=5-1/(V2/2)ˇ2=5-1/0,5 =
=5-2=3
y=3V3/xˇ4,y´=3V3-4/xˇ3
(3V3 značit 3ˇ(1/3)