6. The cost of a car is Rs 500 000, correct to the nearest...

6. The cost of a car is Rs 500 000, correct to the nearest Rs 10 000. State the lowest and the highest possible values for the cost of the car. 7. John takes 24.7 seconds to run a distance of 200 metres. The time is measured correct to the nearest tenth of a second. State the smallest possible value for the time taken by John.

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00:01 Hi there.

00:01 In this question, there are a couple of questions.

00:05 Let me just solve them.

00:07 The first one, the f of x is given.

00:09 Let's say this is the first question.

00:11 Let me just write first here.

00:13 So the f of x is given as this is x minus 8x divided by x plus 2.

00:22 So we have to find the maximum minimum values of this function.

00:26 So what we have to do, first of all, we have to just take the derivative of the function, the first derivative of the function, which we have to find the maximum minimum values of this function.

00:31 So what we have to do, first of the which is 1 minus.

00:33 So there's a division rule here, so we have to apply the division rule.

00:37 The derivative of the top times the bottom and minus the derivative of the bottom times top and divided by x plus 2 squared.

00:46 And set this equation equal to 0.

00:48 Let's simplify the equation.

00:49 We got 1 minus 8x, which is 16 over x plus 2 squared.

00:57 That is equal to 0.

00:58 So let's try to leave alone x plus 2, which is 1 is equal to 16 plus x plus 2 squared.

01:05 So cross multiply, x plus 2 squared, which is equal to 16.

01:09 So from here we got x plus 2 is equal to 4 or x plus 2 is equal to negative 4.

01:15 So from here we got x is equal to 2 and x is equal to negative 6...

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