answer with description please

Quiz 6 Q1 1 Point In big O notation, fu (tx)+ An, "u"(tx ) + At Tu (tx ) + ... is: O O(At) O O(At?) O O(At3 ) Save Answer Q2 1 Point The accumulated error of Forward Euler at the Ath time step, ux - u(t, ) is: O O(At) Different from the truncation error, 7) = 1 : - flu(tx), tx) 0 0(1) Save Answer Q3 1 Point Which of the following is true for an IVP of form & = As that has high stiffness? O At least one of its eigenvalues has no imaginary component O There is a large difference between the largest and smallest eigenvalues O All of its eigenvalues are very small Save