If a1 = 1 and an+1= 2an + 5, n = 1, 2 .. , then a10 is equal to ?	Choose the most appropriate option: A) a. 6*2^9 -5 B) b. 5*2^99+6 C) c. 6*2^99+5 D) d. 6*2^99-5 E) e. 6*2^99-6
Here is solution:   an+1=2an+5............(1)   lets ADD 5 to both sides....   so (an+1) + 5= 2 (an+5)....................taking 2 as common factor   now a1=1. so for n=1, an+5=6.......   putting n=1. we get both sides as,   a2 + 5= 2 * 6 ..............as ( an+5=6 .......(for n=1)..)   a2= 2 *6 - 5   a2= 2 * 2 *3 - 5   a2= 2^2 *3 - 5................. so with same progression   a10= 2^10 * 3 - 5   a10=2* 2^9 * 3 - 5   a10= 6 * 2^9 - 5   a. 6*2^9 -5
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If a1 = 1 and an+1= 2an + 5, n = 1, 2 .. , then a10 is equal to ?