-3/7x²-6/7xy-3/7y² = -3/7(x²+2xy+y²) = -3/7(x+y)²
(2sin6acosa+sin6a)/(2cos6acosa+cos6a)-tg6a+7=
=sin6a(2cosa+1)/cos6a(2cosa+1)-tg6a+7=tg6a-tg6a+7=7
<span>а). 6x^3 – 24x= 0
6x(x^2-4)=0
6x(x-2)(x+2)=0
6x=0 или x-2=0 или x+2=0
x=0 x=2 x=-2
Ответ:</span>x=0 <span>
</span>x=2
x=-2
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</span><span>б). 25x^3- 10x^2 +x =0
</span>x(25x^2-10x+1)=0
x(5x-1)^2=0
x=0 или (5x-1)^2=0
5x-1=0
5x=1
x=1/5
Ответ:x=0
x=1/5
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<span>в). 2x^4 + 6x^3 – 8x^2- 24x = 0
</span>2x^2(x^2-4)+6x(x^2-4)=0
(2x^2+6x)(x^2-4)=0
2x(x-2)(x+2)(x+3)=0
2x=0 или x-2=0 или x+2=0 или x+3=0
x=0 x=2 x=-2 x=-3
Ответ:x=0
x=2
x=-2
x=-3
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