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The sum of the first and third term of a geometric sequence is 72. The sum to infinity of this sequence is 360, find the possible values of the common ratio, r.

We are dealing with a geometric sequence here, we will therefore focus on the geometric sequence formulas that are given in the math HL formula booklet. The first part of the information we are given states ...
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Answered by Armand G. Maths tutor
3453 Views

Solve the simultaneous equations: 2x + y = 18, x - y = 6

Label each equation:2x + y = 18 (1)x - y = 6 (2)Since the y's have the same coefficient (ignoring the signs) you want to cancel the y's to leave just an equation with x.add (1) to (2):3x = 24Then rearrange f...
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Answered by Megan H. Maths tutor
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There are 13 counters in a bag. 4 counters are red, the rest are blue. Alice takes 2 counters without replacing them. What is the probability that both counters are the same colour?

To begin question, we must establish how blue counters there are at the start. This is a simple subtraction calculation.13-4=9There are 4 red counters and 9 blue counters, which totals to 13 counters. Next, ...
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Answered by Austin E. Maths tutor
10690 Views

How do I integrate 4x*exp(x^2 - 1) with respect to x?

During the session I would go step by step through the integration by substitution.
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Answered by Anmol S. Maths tutor
3823 Views

In a school 2/5 students play an instrument. Of those students 3/7 play the violin. Find the ratio of students who play the violin compared to the students who do not play the violin.

First step: Find the number of students out of the whole school who play the violin. 2/5 x 3/7= 6/35 (Simplest version of the fraction) Take the denominator to represent the number of students in the school ...
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Answered by Neha B. Maths tutor
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