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kkk579

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how r u able to tell when a function includes negative infinity or positive infinity without drawing the graph for complex ones like these?
 

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kkk579

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how r u able to tell when a function includes negative infinity or positive infinity without drawing the graph for complex ones like these?
is it just when the inequality sign points to the right it’s positive infinity and when it points to the left it’s negative infinity
or is it smth else
 

pikachu975

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how r u able to tell when a function includes negative infinity or positive infinity without drawing the graph for complex ones like these?
You have x>4 and x>=11 so the common numbers that are included by both of these inequalities is x>=11 aka [11, infinity]. Can't have negative infinity if x is greater than positive numbers.
 

kkk579

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You have x>4 and x>=11 so the common numbers that are included by both of these inequalities is x>=11 aka [11, infinity]. Can't have negative infinity if x is greater than positive numbers.
okay ty so basically if the inequality sign points to the right it’s positive infinity and if it points to the left it’s negative infinity
i just wanted to confirm bcuz my tutor was speaking incredibly fast
 

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