You can only ask one question at a time. I am providing
the value of f'(1).
We have to find the derivative of f(x)
= x^sqrt(x^2+3)+10
Let g(x) =
x^sqrt(x^2+3)
ln (g(x)) = sqrt( x^2 + 3) ln
x
1/(g(x)) * g'(x) = [sqrt( x^2 + 3)]'*ln x + sqrt( x^2 +
3)*[ln x]'
1/(g(x))*g'(x) = (1/2)*2x*(1/sqrt( x^2 + 3))*ln
x + sqrt(x^2 + 3)*(1/x)
g'(x) = [(1/2)*2x*(1/sqrt( x^2 +
3))*ln x + sqrt(x^2 + 3)*(1/x)](x^sqrt(x^2+3))
=>
g'(x) = [x^2*ln x +(x^2 + 3)](x^sqrt(x^2+3))/x*(sqrt( x^2 +
3))
=> g'(x) = [(x^sqrt(x^2+3))*x^2*ln x
+(x^sqrt(x^2+3))(x^2 + 3)](x^sqrt(x^2+3))/x*(sqrt( x^2 +
3))
=> g'(x) = [(x^sqrt(x^2+3)+2)*ln x
+(x^sqrt(x^2+3))(x^2 + 3)]/x*(sqrt( x^2 + 3))
We see that
f'(x) = g'(x) as 10 is a constant.
f'(x) =
[(x^sqrt(x^2+3)+2)*ln x +(x^sqrt(x^2+3))(x^2 + 3)]/x*(sqrt( x^2 +
3))
f'(1) = 1*4/2
=>
f'(1) = 2
The required value of f'(1) =
2.
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