Just go through the following problem(adsbygoogle = window.adsbygoogle || []).push({});

Question 1:find the range of the following function

f(x)=3x^{2}+4 for -4≤x≤3

Answer:

rewriting -4≤x≤3

step1. 0≤x^{2}≤16

step2. multiply 3 for the entire step 1.

step4. add 4 for the entire step1.

step5. 4≤f(x)≤52

so the above problem i have understood

now how do i solve the following problem using the same method as above, because the following problem is a bit different from the first one, and i get a reverse answer

Question 2: find the range of the following function

f(x)=9-2x^{2}for -3≤x≤3

rewriting -3≤x≤3

step 1. 0≤x^{2}≤9 now is this step correct?, i dont think so.

step 2. ????????

step 3. ????????

step 4. ????????

plz note: i cannot find the range directly because each step carries marks

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# Range of a function, very simple & basic question

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