Question

The first four terms of an A.P whose first term is -2 and the common difference is -2 is
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Answer 1

Given :

• first term is -2 and the common difference is -2 is

To find :

• The first four terms of an A.P

solution :

In the given AP, a = -2, d=-2,

t_n = a + (-1) d

t_1 = (-2) + (1 - 1)(-2) = -2

t_2 = (-2) + (2 - 1)(-2)= -4

t_3 = (-2) + (3 - 1)(-2) = -6

t_4 = (-2) + (4 - 1)(-2)= -8

∴ The first four terms of an A.P is -2 , -4 , -6 , -8

Extra formula's :

t_n = a + ( n - 1 ) d

S_n = n/2 [ 2a + ( n - 1 ) d ]

S_n = n/2 ( a + 1 )

Answer 2

Given

• First term is -2 and the common difference is -2

We Find

• First four terms of an A.P

According to the question

( We know = A = -2 , D = -2, )

so,

T_1 = (-2) + (1 - 1 ) (-2) = -2

T_2 = (-2) + (2 - 1 ) (-2) = -4

T_3 = (-2) + (3 - 1 ) (-2) = -6

T_4 = (-2) + (4 - 1 ) (-2) = -8

So, Four Terms are given :-

T_1 = -2

T_2 = -4

T_3 = -6

T_4 = -8

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