X²-6x-3
D=b²-4ac
D=36-4**1*3=48
√D=√48=4√3
X1,2=(-b-+√D)/2a
X1=(6+4√3/2=3+2√3
X2=(6-4√3)/2=3-2√3
Постоять илёчынова трехчлена:
a(x-x1)(x-x2)
1*](x-(3+2√3)]*[(x-(3-2√3)
Odp: множители квадратный трехчлен x2-6x-3 to:
(x-3-2√3)(x-3+2√3)
Итак приступим № 1)=<span>(sinA/cosA)-sinA)/(sinA/cosA)+sinA)=((sinA-sinAcosA)cosa)/(cosA(sinA+sinA cosA))=(sinA(1-cosA))/(sinA(1+cosA))=(1-cosA)/ (1+cosA)
</span>2)(cos²bsin²b-cos²b)/sin²b :(sin²bcos²b-sin²b)/cos²b=cos²b(sin²b-1)/sin²b : sin²b(cos²b-1)/cos²b=cos²b*(-cos²b)/sin²b : sin²b(-sin²b)cos²b= -cos4b/sin²b : -sin^4b/cos²b=cos^4b/sin²b*cos²b/sin^4b=cos^6b/sin^6b=ctg^6b
(tgb+ctgb)(tg²b-tgbctgb+ctg²b)/(tg²b-2tgbctgb+ctg²b-1)=
(tgb+ctgb)(tg²b-1+ctg²b)/(tg²b-2+ctg²b+1)=(tgb+ctgb)(tg²b-1+ctg²b)/(tg²b+ctg²b-1)=
(tgb+ctgb)=(sinbsinb+cosbcosb)/sinb*cosb=(sin²b+cos²b)/1/2sin2b=2/sin2b
4)4)3sin0+2cos0=<u>3x0</u>+2*1 = 0+<span>2= 2 ...так как sin0=0, a cos0=1
</span>
Надеюсь, что понятно, так как украинский не знаю
-5x(x-2)+(x-3)(5x+1)= -5x²+10x+5x²+x-15x-3= 10x+x-15x-3= -4x-3.
3a(a-b)-(a+b)(3a-b)= 3a²-3ab-(3a²-ab+3ab-b²)= 3a²-3ab-(3a²+2ab-b²)= 3a²-3ab-3a²-2ab+b²= -3ab-2ab+b² = -5ab+b².
(2a-b)(3a+b)+(3a-5b)(a-b)= 6a²+2ab-3ab-b²+3a²-3ab-5ab+5b²= 9a²-9ab+4b².
(5x²y-y)(x-2y)-(x²+2y)(5x-3y)= 5x³y-10x²y²-xy+2y²-(5x³-3x²y+10xy-6y²)= 5x³y-10x²y²-xy+2y²-5x³+3x²y-10xy+6y²= 5x³y-10x²y²-11xy+8y²<span>-5x³+3x²y.
3a(a+3)+(2-a)(3a-4)= 3a</span>²+9a+6a+8+3a²+4a= 9a+6a-8+4a= 19a-8.
7x²(x-2y)-(x-y)(7x+y)=7x²-14xy-(7x²+xy-7xy-y²)= 7x²-14xy-(7x²-6xy-y²)= 7x²-14xy-7x²+6xy+y²= -14xy+6xy+y²= -8xy+y².
(3m-2n)(2m-3n)+(3n-m)(2n-m)= 6m²-9mn+4mn+6n²+6n²-3mn-2mn+m²= 7m²-18mn+12n².
(2a-5b²)(a+b)-(b²-2a)(a-5b)= 2a²+2ab-5ab²-5b³-(ab²-5b³-2a²+10ab)= <span>2a²+2ab-5ab²-5b³-ab</span>²+5b³+2a²-10ab= 4a²-8ab-6ab².