Lutasin ang x^19-x^57

$$x ^ { 19 } - x ^ { 57 }$$

I-factor

$$\left(x-1\right)\left(x+1\right)\left(-x^{18}+x^{17}-x^{16}+x^{15}-x^{14}+x^{13}-x^{12}+x^{11}-x^{10}+x^{9}-x^{8}+x^{7}-x^{6}+x^{5}-x^{4}+x^{3}-x^{2}+x-1\right)\left(x^{18}+x^{17}+x^{16}+x^{15}+x^{14}+x^{13}+x^{12}+x^{11}+x^{10}+x^{9}+x^{8}+x^{7}+x^{6}+x^{5}+x^{4}+x^{3}+x^{2}+x+1\right)x^{19}$$

Mga Hakbang ng Solution

I-factor out ang x^{19}.

$$x^{19}\left(1-x^{38}\right)$$

Isaalang-alang ang 1-x^{38}. I-rewrite ang 1-x^{38} bilang 1^{2}-\left(-x^{19}\right)^{2}. Maaaring i-factor ang difference ng mga square gamit ang panuntunang: a^{2}-b^{2}=\left(a-b\right)\left(a+b\right).

$$\left(1+x^{19}\right)\left(1-x^{19}\right)$$

Pagsunud-sunurin ang mga term.

$$\left(x^{19}+1\right)\left(-x^{19}+1\right)$$

Isaalang-alang ang x^{19}+1. Sa Rational Root Theorem, ang lahat ng rational root ng polynomial ay nasa anyong \frac{p}{q}, kung saan hinahati ng p ang constant term 1 at hinahati ng q ang leading coefficient 1. Ang isa sa mga ganoong root ay -1. I-factor ang polynomial sa pamamagitan ng paghahati nito sa x+1.

$$\left(x+1\right)\left(x^{18}-x^{17}+x^{16}-x^{15}+x^{14}-x^{13}+x^{12}-x^{11}+x^{10}-x^{9}+x^{8}-x^{7}+x^{6}-x^{5}+x^{4}-x^{3}+x^{2}-x+1\right)$$

Isaalang-alang ang -x^{19}+1. Sa Rational Root Theorem, ang lahat ng rational root ng polynomial ay nasa anyong \frac{p}{q}, kung saan hinahati ng p ang constant term 1 at hinahati ng q ang leading coefficient -1. Ang isa sa mga ganoong root ay 1. I-factor ang polynomial sa pamamagitan ng paghahati nito sa x-1.

$$\left(x-1\right)\left(-x^{18}-x^{17}-x^{16}-x^{15}-x^{14}-x^{13}-x^{12}-x^{11}-x^{10}-x^{9}-x^{8}-x^{7}-x^{6}-x^{5}-x^{4}-x^{3}-x^{2}-x-1\right)$$

I-rewrite ang kumpletong naka-factor na expression. Hindi naka-factor ang mga sumusunod na polynomial dahil walang anumang rational root ang mga ito: -x^{18}-x^{17}-x^{16}-x^{15}-x^{14}-x^{13}-x^{12}-x^{11}-x^{10}-x^{9}-x^{8}-x^{7}-x^{6}-x^{5}-x^{4}-x^{3}-x^{2}-x-1,x^{18}-x^{17}+x^{16}-x^{15}+x^{14}-x^{13}+x^{12}-x^{11}+x^{10}-x^{9}+x^{8}-x^{7}+x^{6}-x^{5}+x^{4}-x^{3}+x^{2}-x+1.

$$x^{19}\left(x+1\right)\left(x^{18}-x^{17}+x^{16}-x^{15}+x^{14}-x^{13}+x^{12}-x^{11}+x^{10}-x^{9}+x^{8}-x^{7}+x^{6}-x^{5}+x^{4}-x^{3}+x^{2}-x+1\right)\left(x-1\right)\left(-x^{18}-x^{17}-x^{16}-x^{15}-x^{14}-x^{13}-x^{12}-x^{11}-x^{10}-x^{9}-x^{8}-x^{7}-x^{6}-x^{5}-x^{4}-x^{3}-x^{2}-x-1\right)$$

I-evaluate

$$x^{19}-x^{57}$$