How to find complementary function,#case-1, Rules for finding complementary function,

How to find complementary function , how to find CF, how to find Yc , how to find ϕ(D),
how to find LDE #case 1, Example of LDE,

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1) How to find quadratic equation
on scientific calculator

2)Conversion of polar to rectangular and
rectangular tu polar

3) How to solve inverse matrix on
scientific calculator