Ответ:
Объяснение:
1.
a) 39x³y/26x²y²=1,5x/y
b)
5y/(y²-2y)= 5y/((y(y-2))= 5/(y-2)
c)
(3a-3b)/(a²-b²)= 3(a-b)/(a-b)(a+b)=3/(a+b)
2.
a)
(3-2a)/2a - (1-a²/a ) = [a(3-2a)-2(1-a²)]/2a² = (3a-6a²-2+2a²)/2a²=
=(-4a²+3a-2)/2a²
b)
1/(3x+y) - 1/(3x-y) =[3x-y-(3x+y)/(9x²-y²)= (3x-y-3x-y)/(9x²-y²)=
=-2y/(9x²-y²)
c)
(4-3b)/(b²-2b) +3/(b-2)= (4-3b)/b(b-2) + 3/(b-2)=(4-3b+3b)/b(b-2)=
=4/(b²-2b)
...=cosx*cosy+sinx*siny-sinx*siny=cosx*cosy
A) m^2-9=(m+3)(m-3)
б) 4-a^2c^2=2^2-(ac)^2=(2-ac)(2+ac)
в) x^3+8=(x+2)(x^2-8x+64)
<span> f(x)=ctg 1/x f'(x)=-1/sin</span>²(1/x) * [-1/x²]