Determina el valor numérico de los siguientes polinomios
![](https://es-static.z-dn.net/files/d2d/11f214fabcf56d1956c9466dfdad18fd.jpg)
Respuestas a la pregunta
Respuesta:
a) 3x-y = 3(-2) -1/3 = -6 -1/3 = -19/3
b) 2x^2y -3x = 2(-2)^2(1/3) -3(-2) = 2/3 (4) +6 = 8/3 +6 = 26/3
c) 8x^2 -5x +9 = 8(-2)^2 -5(-2) +9 = 8(4) +10 +9 = 32 +19 = 51
d) x^2 +y^2 +z^2 = (-2)^2 +(1/3)^2 +(-5)^2 = 4 +1/9 +25 = 29 +1/9 = 262/9
e) 9x^2y^3z +2xy^2z^2 -10 = 9(-2)^2(1/3)^3(-5)+2(-2)( 1/3)^2(-5)^2-10 = -45(4)( 1/27) -4(1/9)(25)-10 = 180(1/27) -100(1/9) -10 = 20/3 -100/9 -10= -40/9 -10 = -130/9
f) 3x^2y -5xy^2 +x -3y +2 = 3(-2)^2(1/3) -5(-2)( 1/3)^2 -2 -3(1/3) +2 = 3/3 (4) +10(1/9) -2 -3/3 +2 = 1(4) +10/9 -2 -1 +2 = 4 +10/9 -3 +2 = 6 -17/9 = 37/9
g) 2xyz -8x +3z +4y = 2(-2)( 1/3)(-5) -8(-2) +3(-5) +4(1/3) = -4(-5/3) +16 -15 +4/3 = 20/3 +1 +4/3 = 8 +1 = 9
h) 1/2x^2y -3/2xy^2 +1/5y = 1/2(-2)^2(1/3) -3/2(-2)( 1/3)^2 +1/5(1/3) = 1/6(4) +2(1/9) +1/15 = 2/3 +2/9 +1/15 = 8/9 + 1/15 = 43/45
i) 3/4x^3y^2z -7/2x^2y^3z^2 +1/5xy^4z = 3/4(-2)^3(1/3)^2(-5) -7/2(-2)^2(1/3)^3(-5)^2 +1/5(-2)( 1/3)^4(-5) = -15/4(-8)( 1/9) -7/2(4)( 1/27)(25) -2/5(1/81)(-5) = 30(1/9) -14(25/27) -2/405(-5) = 10/3 -350/27 +2/81 = 272/81 -350/27 = -778/81
j) -1/5y^2z +1/3yz^2 +1/2y -3 = -1/5(1/3)^2(-5) +1/3(1/3)(-5)^2 +1/2(1/3) -3 = 1(1/9) +1/9(25) +1/6 – 3 = 1/9 +25/9 +1/6 -3 = 26/9 -17/6 = 1/18
Espero que te haya servido de ayuda.