mathsbrain
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Can anyone provide the working for below? Tysm
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question on increasing function (1 Viewer)
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This question should be straightforward if you understand it. All it is asking is what is the domain of f(g(x)).
mathsbrain
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What is the answer you are getting?
[1, 3.5]
mathsbrain
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hmm i tried a few times still not sure how to do it, don't we find the domain of g(x) and intersect with domain of f(g(x))?
So you have been given the domain of g. When it say map [1, 4] to [2, 6] this means [1, 4] is the domain and [2, 6] is the range of g. Actually the question does not explicitly state the domain of g but without making that assumption the question is not doable.
I stg I'm doing all these and everything is all normal and then I come on here and you have these wack ass questions mathsbrain
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So we are looking for domain of f(g(x)), x values of g only makes sense if x values are within 1 to 4.
then f takes the y values of g as its x values, which means f takes values between [2,6] but domain of f is [0,5], so surely that means f takes values from 2 to 5? so I'm not sure how you are getting 3.5?
No, you want find {x : 0<= g(x) <= 5}. Notice x = 3.5 satisfies the condition.
#so surely that means f takes values from 2 to 5? so I'm not sure how you are getting 3.5?
This is not what the question is asking. When we consider domain we need to consider values of x not g(x).