The derivative of x3+2x is 3x2+2.
Steps:
To find the derivative of f(x)=x3+2x, we apply the sum rule and the power rule for differentiation.
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Derivative of x3: Using the power rule, dxd(xn)=nxn−1.
dxd(x3)=3x3−1=3x2.
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Derivative of 2x: Using the constant multiple rule and the power rule.
dxd(2x)=2⋅dxd(x1)=2⋅1x1−1=2⋅1x0=2⋅1=2.
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Sum Rule: The derivative of a sum of functions is the sum of their derivatives.
dxd(x3+2x)=dxd(x3)+dxd(2x)
dxd(x3+2x)=3x2+2.