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n^9*m^2√(-m)
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1)4(3y-4)+5y=1
12y-16+5y=1
17y=1+16
17y=17
y=17/17
y=1
x=3*1-4=3-4=-1
2)3x+4(2x+3)=1
3x+8x+12=1
11x=1-12
11x=-11
x=-11/11
x=-1
y=2*(-1)+3=-2+3=1
Sin²x+sin²y+2cos(x+y+x-y)/2*cos(x+y-x+y)/2=
=sin²x+sin²y+1/2(cosx(x+y-x+y)+cos(x+y+x-y))=
=sin²x+sin²y+1/2(cos2x+cos2y)=sin²x+sin²y+1/2-sin²x+1/2-sin²y=1
У'(х)=4х^3 + 9х^2
Вот решение