Q.5.Solve the equations-4+(-11+2++x= 437.

1.	Q.5.Solve the equations-4+(-11+2++x= 437.
Answer» It is an arithmetic seriesa = -4, d = +3-4 - 1 + 2 +..... + x = 437 Sum of the series Sn=> [2a + (n-1)d ]n /2 = 437 [ -8 + 3(n-1) ] n /2 = 437 - 11n + 3n² = 874 3 n² -11n - 874 = 0 n =(11 + 103 )/6 = 114/6 = 19 (as n is +ve only) So x = a + (n-1)d x = -4 + 3 (19-1) = 50

Answer»

It is an arithmetic seriesa = -4, d = +3-4 - 1 + 2 +..... + x = 437

Sum of the series Sn=> [2a + (n-1)d ]n /2 = 437 [ -8 + 3(n-1) ] n /2 = 437 - 11n + 3n² = 874 3 n² -11n - 874 = 0 n =(11 + 103 )/6 = 114/6 = 19 (as n is +ve only)

So x = a + (n-1)d x = -4 + 3 (19-1) = 50

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Q.5.Solve the equations-4+(-11+2++x= 437.

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