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If x is real, the minimum value of 4x2 + 4x + 9 is
- A4/3
- B8
- C0
- D9
Answer not set
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CCommunity
To find minimum value of 4x2 + 4x + 9:
Let’s arrange the given equation in perfect square form.
4x2 + 4x + 9 = (2x)2 + 2 × 2x + 9
⇒ 4x2 + 4x + 9 = (2x)2 + 2 × 2x × 1 + (1)2 + 8
⇒ 4x2 + 4x + 9 = (2x + 1)2 + 8
? minimum value of any square term is 0, minimum value of given expression = 0 + 8 = 8
Let’s arrange the given equation in perfect square form.
4x2 + 4x + 9 = (2x)2 + 2 × 2x + 9
⇒ 4x2 + 4x + 9 = (2x)2 + 2 × 2x × 1 + (1)2 + 8
⇒ 4x2 + 4x + 9 = (2x + 1)2 + 8
? minimum value of any square term is 0, minimum value of given expression = 0 + 8 = 8