If 18Cx = 18Cx+2, Find x. - Vidyadip

Question

If ¹⁸C_x = ¹⁸C_x+2, Find x.

✓

Answer

We have,

If ⁿC_p = ⁿC_q = n

Then p + q = n

Also,

¹⁸C_x = ¹⁸C_x+2

⇒ x + x + 2 = 18

2x + 2 = 18

2x = 18 - 2

2x = 16

x = 8

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