X√13/2
i is help chu i hope
F(x) = x^(3/2) +3
f'(x) = (3/2)x^(1/2)
f''(x) = (1/2)*(3/2)*x^(-1/2)
f''(x) = 3/(4√x)
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If you mean f(x) = x√(x+3), parentheses are needed (or you need to typeset the expression).
150*0.8 = 120
200*.75= 150, three quarters of 200 is larger