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Outline Descartes’ ‘evil deceiver’ argument and explain what he then says about his knowledge of his own existence.

Descartes suggests, that if we assume that there is an evil power, who's only goal is to deceive us, exists, then we can not be certain about the nature of our reality. He uses many examples. In one of th...

Answered by • Philosophy tutor

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A curve C has equation y = x^2 − 2x − 24 x^(1/2), x > 0 (a) Find (i) dy/d x (ii) d^2y/dx^2 (b) Verify that C has a stationary point when x = 4 (c) Determine the nature of this stationary point, giving a reason for your answer.

(a) i) dy/dx= 2x-2-12x^-1/2ii) d²y/dx²= 2+6x^-3/2(b) Substitute x=4 into dy/dx= 2x-2-12x^-1/2 Show that dy/dx= 0 and state 'hence there is a stationar...

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What was the most significant reason for the success of the First Crusade?

On July 15th 1099 Jerusalem, recently captured by the Fatimids of the Egyptian Sultan, Al-Musta'li, fell to the crusaders. With their victory, three years of campaign came to a victorious end; the assuran...

Answered by Gareth C. • History tutor

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Describe the Cognitive Interview. (6 marks).

The cognitive interview is an interview technique used in order to aid memory and improve accuracy of eye witness statements. The interview consists of four aspects: 'recall everything', 'reverse the orde...

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f ( x ) = 2 x ^3 − 5 x ^2 + ax + a. Given that (x + 2) is a factor of f ( x ), find the value of the constant a. (3 marker)

If x+2 is definitely a factor, that means when we sub x=-2 in, we should get 0 at the end. So 2(-2)^3 - 5(-2)^2 + a(-2) + a = 0So -16 -20= aso a = -36

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