What is the minimum or maximum value of 3x2 + 30x + 7?1. -762. -673. -

1.	What is the minimum or maximum value of 3x2 + 30x + 7?1. -762. -673. -894. -68
Answer» Correct Answer - Option 4 : -68 Given: Our given equation is 3x2 + 30x + 7 Concept used: For maximum and minimum value, we can put dy/dx = 0 And if d2y/dx2 > 0 then the value of x obtained from dy/dx will give minimum value when substituted in equation And if d2y/dx2 < 0 then the value of x obtained from dy/dx will give maximum value when substituted in equation Calculation: Let y = 3x2 + 30x + 7 ⇒ dy/dx = 6x + 30 = 0 ⇒ x = -5 Now, d2y/dx2 = 6 > 0, y will give minimum value at x = -5 ymin = 3(-5)2 + 30 × (-5) + 7 = -68 ∴ The minimum value of given expression is -68

What is the minimum or maximum value of 3x2 + 30x + 7?1. -762. -673. -894. -68

Answer» Correct Answer - Option 4 : -68

Given:

Our given equation is 3x2 + 30x + 7

Concept used:

For maximum and minimum value, we can put

dy/dx = 0

And if d2y/dx2 > 0 then the value of x obtained from dy/dx will give minimum value when substituted in equation

And if d2y/dx2 < 0 then the value of x obtained from dy/dx will give maximum value when substituted in equation

Calculation:

Let y = 3x2 + 30x + 7

⇒ dy/dx = 6x + 30 = 0

⇒ x = -5

Now, d2y/dx2 = 6 > 0,

y will give minimum value at x = -5

ymin = 3(-5)2 + 30 × (-5) + 7 = -68

∴ The minimum value of given expression is -68

Discussion

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