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4. Let f(x) = x2 - 81. Find f'(x). (1 point)

O
+ Vx+81
09x
w
1
x2 -81
81

User Juliean
by
3.1k points

1 Answer

1 vote

Here we are given that ;


{:\implies \quad \sf f(x)=x^(2)-81}

Differentiating both sides w.r.t.x ;


{:\implies \quad \sf f^(\prime)(x)=(d)/(dx)(x^(2)-81)}


{:\implies \quad \sf f^(\prime)(x)=(d)/(dx)(x^(2))-(d)/(dx)(81)}


{:\implies \quad \sf f^(\prime)(x)=2x^(2-1)-0}


{:\implies \quad \bf \therefore \quad \underline{\underline{f^(\prime)(x)=2x}}}

This is the required answer

User Corbett
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3.2k points