x的四次方加4分解因式?怎麼做啊?大神們幫幫忙

x的四次方加4分解因式?怎麼做啊?大神們幫幫忙


X^4+4 =X^4+4x^2-4X^2+4 =(X^4+4x^2+4)-4X^2 =(X^2+2)^2-4X^2 =(X^2+2-2X)(X^2+2+2X)



分解因式(1)(m+n)三次方+2m(m+n)+m(m+n)要過程,


(m+n)^3+2m(m+n)^2+m^2(m+n)=(m+n)[(m+n)^2+2m+m^2] =(m+n)[(m+n)+m]^2 =(m+n)(2m+n)^2



已知x的四次+mx的三次方+nx-16有因式x-1和x-2,求m和n的值,並將這個多項式分解因式大神們幫幫忙
如題


設x4+mx3+nx-16=(x-1)(x-2)(x2+ax+b)=(x2-3x+2)(x2+ax+b)得2b=-16 b-3a+2=0 b=-8 a=-2(x-1)(x-2)(x2-2x-8)=(x-1)(x-2)(x-4)(x+2)=x4-5x3+20x-16 m=-5 n=20