Can anyone answer and explain the question: Find the intervals on which x satisfies x^{2}+8x>0
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Factor out x and use the fact that the product is positive iff both factors have the same sign.
Is this the right answer? im unsure of what the correct answer format is x<-8 makes expression positive -8<x<0 makes expression negative 0<x makes expression positive
Originally Posted by emakarov Factor out x and use the fact that the product is positive iff both factors have the same sign. Is this the right answer? im unsure of what the correct answer format is x<-8 makes expression positive -8<x<0 makes expression negative 0<x makes expression positive
Yes, this is the right answer. Since you only need to find when x^{2} + 8x > 0, the answer is x < -8 or x > 0. Alternatively, written as a union of intervals, x ∈ (-∞, -8) ∪ (0, ∞).
Thanks very informative and helpful!
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