Answer:
the linearization is y = 1/4x +5/4
the linearization will produce <em>overestimates</em>
the values computed from this linearization are ...
f(3.98) ≈ 2.245
f(4.05) ≈ 2.2625
Step-by-step explanation:
Apparently, you have ...

from which you have correctly determined that ...

so that f(3) = 2 and f'(3) = 1/4. Putting these values into the point-slope form of the equation of a line, we get the linearization ...
g(x) = (1/4)(x -3) +2
g(x) = (1/4)x +5/4
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The values from this linearization will be overestimates, as the curve f(x) is concave downward everywhere. The tangent (linearization) is necessarily above the curve everywhere.
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At the given values, we find ...
g(3.98) = 2.245
g(4.05) = 2.2625
Dividing fractions is the same as multiplying by its reciprocal so you can change the equation to this

And you can simplify by eliminating the fours and multiplying straight across

You can pull out - 7 from the top and 2 from the bottom so you have this

And then you can cancel out to (2-x) to get an answer of
11 drinks because 85x11 = £9.35
Answer:
Step-by-step explanation:
do the thing times 2