Question

Add polynomials
0.15x^4 + 0.10x^3
- 0.01x^3 + 0.01x^2 + x
1.25x^4 + 0.11x^2 + 0.01
027x^3 + 0.99
-0.35x^4 + 15x^2 - 0.03

I don't understand PLEASE PLEASE HELP!!

Answer 1

Just as you have to line up the decimal places with numbers, you can only add like powers with polynomials.

So, add up all the terms with x^4: (0.15 + 1.25 - 0.35) = 1.05
Add up all the x^3 terms: (0.10 -0.01 + 0.27) = 0.36 (assuming 027x^3 should be 0.27)
Add up the x^2 terms: (0.01 + 0.11 + 0.15) = 0.27 (assuming 15x^2 should be .15)
Add up all the x terms: (1) = 1
Add up the plain numbers: (0.01 + 0.99 - 0.03) = 0.97

Put it all together to get
1.05x^4 + 0.36x^3 + 0.15x^2 + x + 0.97

If my assumptions about decimal places are wrong, adjust things as needed.