Verify that the function defined by ` y = sinx - cosx` is a solution of the initial value problem `dy / dx = sinx +cosx`; such that `y(0) = -1`

Explanation

`frac{d y}{d x}=sin x+cos x `




`d y=(sin x+cos x) d x`


This is variable seperable equation

`

int d y=int(sin x+cos x) d x`

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