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Arithmetic Progression is a sequence of such numbers whose difference of two consecutive terms is constant. Constant quantity is known as common difference. It is represented by letter ‘d’. | |||||||
For example: Following sequences are n arithmetic progression. | |||||||
1, 2, 3, 4, …. (common difference = -1) | |||||||
8, 5, 2, -1, -4, ... (common difference = -3) | |||||||
a, a - d, a - 2d, a - 3d, …. (common difference = -d) |
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If first term of an arithmetic progression is a and common difference is d, then: | |||||||
nth term of arithmetic progression = a + (n – 1)d | |||||||
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Arithmetic mean of two terns a and b | |||||||
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If nth term of series is a linear expression, then that series will be arithmetic progression. |
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If sum of n terms of any series is quadratic expression, then that series will be arithmetic progression. | |||||||
If same quantity is added or subtracted from each term of an arithmetic progression, then new series formed will also be an arithmetic progression. | |||||||
If same quantity is multiplied or divided by each term of an arithmetic progression then new series formed will also be an arithmetic series. | |||||||
If corresponding terms of two series are added or subtracted then new series formed will be also an arithmetic series. | |||||||
Series formed by multiplying or dividing corresponding terms of two arithmetic progression, then series formed will be not an arithmetic series. | |||||||