I need help with q17 part b, d and e pls
For b, use the derivative of cos^-1(x) formula
For d,
when x > 1 then the equation given is just positive x instead of abs value x
when x < 1 then equation given is just negative x instead of abs value x
For e,
For x > 1,
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this is simply going to be positive as the denom will always be positive as
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and
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and as the derivative is positive for all values x > 1, hence it increases for x > 1
For x < 1,
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will be negative as x is a negative value multiplying the positive value from
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and therefore the denom is negative. As there is a negative outside, that will multiply with the negative value inside the brackets and hence will always produce a positive value. Hence it is increasing for this domain as well. This is just elaboration, I would just do;
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as x < 0 and
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so denominator is > 0 within the domain
Therefore function is increasing for x < -1