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- Homework Statement
- Classify the second order linear pde, given by;

##U_t +2U_{tt}+3U_{xx}=0##

- Relevant Equations
- use of discriminant

Now i learned how to use discriminant i.e ##b^2-4ac## and in using this we have;

##b^2-4ac##=##0-(4×3×2)##=##-24<0,## therefore elliptic.

The textbook has a slight different approach, which i am not familiar with as i was trained to use the discriminant at my undergraduate studies...

see textbook approach here;

and the textbook solution is here;

and i also checked wikipedia on this and they have used the discriminant approach. See the approach here; ( i am comfortable with this approach)

Both approaches should be fine, one can use either approach...correct?

##b^2-4ac##=##0-(4×3×2)##=##-24<0,## therefore elliptic.

The textbook has a slight different approach, which i am not familiar with as i was trained to use the discriminant at my undergraduate studies...

see textbook approach here;

and the textbook solution is here;

Both approaches should be fine, one can use either approach...correct?