1. You must show all your working. (click for each stage of the answer)
The equation x3 +10x=51 has a solution between 2 and 3. Use a trial and improvement
method to find this solution. Give your answer correct to 1 decimal place.
You must show all your working. (click for each stage of the answer)
First we test a value which is half way between 2 and 3, x=2.5
is too small
Then we test a value which is between 2.5 and 3, say x=2.7
is too small
We then try another value between 2.7 and 3, say x=2.8
is too small
is too big
We test x=2.9
To decide if we should take 2.8 or 2.9 we test the value in the middle
is too big
Because the answer is too big we will choose the smaller value namely x=2.8 as our solution to one decimal place.
You must show all this working out to gain full points for this question in the exam
The equation x3 – 4x=24 has a solution between 3 and 4. Use a trial and improvement
method to find this solution. Give your answer correct to 1 decimal place. You must
Show all your working.
Try x=3.5
too big
Try x=3.2
too small
Try x=3.3
too small
Try x=3.4
too big
To decide if we should take 2.8 or 2.9 we test the value in the middle
Try x=3.35
too big
Because the answer is too big we will choose the smaller value namely x=3.3 as our solution to one decimal place.