a) W(x)+Q(x)=x3−x2+6x−2+2x3−x2+x+4=3x3−2x2+7x+2
W(x)−Q(x)=x3−x2+6x−2−(2x3−x2+x+4)=x3−x2+6x−2−2x3+x2−x−4=−x3+5x−6
b) W(x)+Q(x)=3x3−5x2+7x−1−4x3+2x2−x+5=−x3−3x2+6x+4
W(x)−Q(x)=3x3−5x2+7x−1−(−4x3+2x2−x+5)=3x3−5x2+7x−1+4x3−2x2+x−5=7x3−7x2+8x−6
c) W(x)+Q(x)=−3x4+2x3−x+3+x5+4x3+2x−1=x5−3x4+6x3+x+2
W(x)−Q(x)=−3x4+2x3−x+3−(x5+4x3+2x−1)=−3x4+2x3−x+3−x5−4x3−2x+1=−x5−3x4−2x3−3x+4
d) W(x)+Q(x)=4x5−6x3+11+4x5+6x3+3=8x5+14
W(x)−Q(x)=4x5−6x3+11−(4x5+6x3+3)=4x5−6x3+11−4x5−6x3−3=−12x3+8
e) W(x)+Q(x)=12x4−3x+1−5x4+3x2−1=7x4+3x2−3x
W(x)−Q(x)=12x4−3x+1−(−5x4+3x2−1)=12x4−3x+1+5x4−3x2+1=17x4−3x2−3x+2
f) W(x)+Q(x)=21x5+23x2−25x−23x3−25x2+21x−1=21x5−23x3−x2−2x−1
W(x)−Q(x)=21x5+23x2−25x−(−23x3−25x2+21x−1)=21x5+23x2−25x+23x3+25x2−21x+1=21x5+23x3+4x2−3x+1
g) W(x)+Q(x)=0,3x3−0,7x2+0,1x+3,1−2,7x3+1,7x2−0,9x+2,1=−2,4x3+x2−0,8x+5,2
W(x)−Q(x)=0,3x3−0,7x2+0,1x+3,1−(−2,7x3+1,7x2−0,9x+2,1)=0,3x3−0,7x2+0,1x+3,1+2,7x3−1,7x2+0,9x−2,1=3x3−2,4x2+x+1
h) W(x)+Q(x)=3x4−0,2x3−x2+1,1x−7+0,8x3+2x2−3,9x+1=3x4+0,6x3+x2−2,8x−6
W(x)−Q(x)=3x4−0,2x3−x2+1,1x−7−(0,8x3+2x2−3,9x+1)=3x4−0,2x3−x2+1,1x−7−0,8x3−2x2+3,9x−1=3x4−x3−3x2+5x−8