2) (-7/5)^-1 = -5/7
4) (7/8)-² =(8/7)² =64/49 =1 15/49(одна целая пятнадцать сорок девятых)
6) (-3/5)^-3 =(-5/3)^3 =(-125/27) = -4 17/27
2) (0.3)^-4 =(3/10)^-4 =(10/3)^4 =10000/81 =123 37/81
4) (-0.7)-² =(-7/10)-² =(-10/7)² =100/49 =2 2/49
6) -(-0.9)-² = -(-9/10)-² = -(-10/9)² = -100/81 = -1 19/81
8) (2.1)-² =(21/10)-² =(10/21)² =100/441
2) (-3)^-3. -(1/2)^-4 =(-1/3)^3 -2^4 = -1/27 -16 =(-16 -27*16) /27*16 = -448 /432
4) (2/7)^-3 +(-2)^-5 =(7/2)^3. -(1/2)^5 =343/8 -1/32 =(343*4 -1)/32 =1371/32 =42 27/32
2) =5x^4*6.2x²y^5 /y^3 =31x^6*y²
4) =1.5y*y. /x^3*6.2x^4 =1.5y² /6.2x^7
6) =4m^3 /0.2*1*n^3*n^3 =4m^3 /0.2n^6 =20m^3 /n^6; (m^0=1)
По теореме Виета
х1+х2 = -b и х1*х2 = с, при этом а= 1
b= - (x1+x2) = -(1-2√3+1+2√3) = -2
c= x1*x2 = (1-2√3)*(1+2√3) = 1-7 = -6
значит уравнение:
х^2 -2x-6 = 0
X1+x2=-p
(x1-x2)=81
x1*x2=90
x1=90/x2
(90/x2-x2)²=81
90/x2-x2=-9 U 90/x2-x2=9
1)(x2)²-9x2-90=0
(x2)1+(x2)2=9 U (x2)1*(x2)2=-90
(x2)1=-6⇒(x1)1=-15
(x2)2=15⇒(x1)2=6
p1=_(-6-15)=21
p2=-(6+15)=-21
2)(x2)²+9x2-90=0
(x2)1+(x2)2=-9 U (x2)1*(x2)2=-90
(x2)1=-15⇒(x1)1=-6
p3=-(-15-6)=21
(x2)2=6⇒(x1)1=15
p4=-(6+15)=-21
Ответ р=-21 или р=21