Hi,
Can someone please help me understand the following questions and how are they different?
1. If g(x) = 3x + x^1/2, what is the value of g(d2 + 6d + 9)?
In the above question they have taken both (d+3) and -(d+3) for x^1/2 to solve the equation
2. if x is negative and y is positive, what is (4x^2−4xy+y^2)^1/2
In this question it is mentioned that the number under root will only take positive value.
Can someone explain me what is the difference. From the rule i know if you have (x^2)^1/2 you can take both negative and positive values for x then shouldn't both these questions have both negative and positive value? Can someone please explain
thank you.
square roots doubt
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- sanju09
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Power HALF refers to √, which means positive (by and large non-negative) root only; so NO - (d + 3) be considered. The basic function concepts are occasionally tested on GMAT. Remember, whatever is d + 3 or 2x - y in sign, positive or negative; their whole squares are non-negatives.ahahkhyati.j wrote:Hi,
Can someone please help me understand the following questions and how are they different?
1. If g(x) = 3x + x^1/2, what is the value of g(d2 + 6d + 9)?
In the above question they have taken both (d+3) and -(d+3) for x^1/2 to solve the equation
2. if x is negative and y is positive, what is (4x^2−4xy+y^2)^1/2
In this question it is mentioned that the number under root will only take positive value.
Can someone explain me what is the difference. From the rule i know if you have (x^2)^1/2 you can take both negative and positive values for x then shouldn't both these questions have both negative and positive value? Can someone please explain
thank you.
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Sanjeev K Saxena
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Lucknow-226001
www.manyagroup.com
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The first question seems flawed - do you have the complete text, with solutions? It'd be helpful to see.