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anonymous
 5 years ago
how do i solve this polynomial inequality, (x4)(x+2)>0?
anonymous
 5 years ago
how do i solve this polynomial inequality, (x4)(x+2)>0?

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myininaya
 5 years ago
Best ResponseYou've already chosen the best response.2find where it is zero first and then make a little chart for numbers before and after each zero

myininaya
 5 years ago
Best ResponseYou've already chosen the best response.2k so x=4 and x=2 2 comes before 4 so choose any number before 2 to see what happens to the factors btw inf..2 choose any number in btw 2 and 4 to see what happens to the factors between 2..4 choose any number after 4 to see what happens to the factors after 4..inf

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0simple enough. thanks

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0x4 > 0 x > 4 and x + 2 > 0 x < 2 therefore, the solutions are (infinity, 2) union (4, +inifinity)

myininaya
 5 years ago
Best ResponseYou've already chosen the best response.2so lets the first interval i have listed choose a number before 2 like 4 so 44= and 4+2= a negative time a negative is a positive so (inf,2) is part of your answer now 2nd interval choose a number between 2 and 4 like 0 04= 0+2=+ a negative times a positive is negative so (2,4) is not apart of our answer now last interval choose a number btw 4..inf like 5 54=+ 5+2=+ a postive times a postive= positive so (4,inf) is apart of our answer so our answer is x is an element of (inf,2)U(4,inf) notice i didnt include the 2 and 4 because the inequality did not have a line underneath

myininaya
 5 years ago
Best ResponseYou've already chosen the best response.2i didn't realize someone had posted i was so busy lol

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0what about x^25x+4>0 would it then be x1>0 and x4>0?

myininaya
 5 years ago
Best ResponseYou've already chosen the best response.2i would do (x4)(x1)>0 x=4 and x=1 is when LHS is 0 so 1 comes before 4 so choose a number before 1 like 0 we have 01=1 and 04=4 (1)(4)>0 so (inf,1) is part of our answer now choose a number btw 1 and 4 like 2 we have 21=1 and 24=2 so 1(2)=2<0 so (1,4) is not part of answer now we choose our final test number after 4 like 100 we have 1001=99 and 1004=96 and (99)(96)>0 so (4,inf) is apart of our answer our answer is (inf,1)U(4,inf)

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0so you choose a point before the first term. if it is true in the equation all numbers before that term will be included? then you choose a number between the two terms and if it is not true no numbers between the terms will be included? then you choose a number after the larger term, if it is true all terms larger than the greater term will be true?
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