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Is AB perpendicular to BC where A =(2,0,-1), B=(4,3,-6) and C = (9,3,-4)

AB = B - A = (4,3,-6)- (2,0,-1) = (2 , 3 , -5)BC = C - B = (9,3,-4) - (4,3,-6) = (5, 0 , 2) If perpendicular "AB dot BC" should equal zeroAB dot BC = (2,3,-5) dot (5,0,2) = (2x5) + (3x0) + (-5x2) =...
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Answered by Syed Usman B. Maths tutor
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Factorise: x^2+2x-3

think of it in the form of Ax^2 +Bx +C. Most of the GCSE examples will have A as zero so we will ignore the A. To factorise this you need to find what two numbers multiply to make C and adds to make B. In th...
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Answered by Katherine A. Maths tutor
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Solve x^2-5x+6=0

To solve this, we need to factorise the expression (write as a product of two brackets). To do this we want to find to numbers that multiply to make +6 and add up to -5, for this case. These numbers turn out...
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Answered by Samuel P. Maths tutor
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Write down the value of 36^0.5

We know that the question is asking us to take the number 36 to the power of 0.5. By assumption 0.5 can be written as 1/2. To take 36 to the power of a 1/2 we take it to the root of the denominator and then ...
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Answered by Thusikan V. Maths tutor
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A bag contains 5 red beads and 7 blue beads. Two beads are removed at random without replacement. Workout the probability that the two beads are the same colour.

This question is most simply solved with a probability tree diagram, where you just follow the paths of picking two same coloured beads. The first branch would be picking two red beads. P(R1) = 5 / 12, and P...
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Answered by Will M. Maths tutor
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