a) f(x)+g(x) = 2x4 -x3 -2x2+x+4
b) f(x)-g(x) =x3-4x2+x-5
Giải thích các bước giải:
a) f(x)+g(x)=x4x4 – 3x23x2 + x – 1 + x4x4 - x3x3 + x2x2 + 5
=2x42x4 - x3x3 -2x22x2 +x +4
b)f(x)-g(x)=x4x4 – 3x23x2 + x – 1 - x4x4 + x3x3 - x2x2 - 5
= x3x3 - 4x24x2 +x -6
a) f(x)+g(x)=(\(x^4\)-\(3x^2\)+x-1)+(\(x^4\)-\(x^3\)+\(x^2\)+5)
=(\(x^4\)+\(x^4\))+(\(-3x^2\)+\(x^2\))+(-1+5)-\(x^3\)+x
=\(2x^4\)-\(2x^2\)+4-\(x^3\)+x
b) f(x)-g(x)=(\(x^4\)-\(3x^2\)+x-1)-(\(x^4\)-\(x^3\)+\(x^2\)+5)
=(\(x^4\)-\(x^4\))+(\(-3x^2\)-\(x^2\))+(-1-5)+\(x^3\)+x
=-\(4x^2\)-6+\(x^3\)+x