If `y=x^4-10` and if `x` changes from 2 to 1.99, what is the approximate change in `y ?` Also, find the changed value of `ydot`

Explanation

Let `x=2,x+deltax=1.99`

` deltax=1.99-2=-0.01`

Now,`y=x^4-10`

`(dy/dx)=4x^3`

`(dy/dx)_(x=2)=32`

Now,

`dy=(dy/dx)dx=32(-0.01)=-0.32`

Or `Deltay=-0.32`

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