Hi i have to read mathematics over 7 years and now i cant even solve a simple equation(adsbygoogle = window.adsbygoogle || []).push({});

1. The problem statement, all variables and given/known data

I hav3e the following

x(t)=-3t for t<0 and

x(t)=t t>=0

I want to calculate the x(t)+x(-t) for t<0 firstloy and then for t>=0

2. Relevant equations

3. The attempt at a solution

For t<0

x(t)+x(-t)=-3t+t (x(t)=-3t cause x is negative x(-t)=t cause the negative of the negative -t is the t which is t)

The problem is that my teachers book says that x(t)+x(-t)=-3t-t and i cant understand how he calculates that

Now for t>=0 x(t)+x(-t)=t-3t (x(t)=t cause it is positive and x(-t)=-3t cause the negative of t>=0 is the t<0 which makes x(t)=-3t..

My teacher again argues with me cause he calculates in his note

x(t)+x(-t) as =t+3t

So what i am doing wrong ?:(

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# Homework Help: Calculate simple equation

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