Question

If the term of an A.P is 2n + 5, find the first term of A.P. 4

Answer 1

Step-by-step explanation:

first term of AP is=2(1)+5=7

Answer 2

Answer:

$\huge{\pink{\boxed{\green{\sf{a=7}}}}}$

$\huge{\pink{\boxed{\green{\sf{d=2}}}}}$

$\huge{\pink{\boxed{\green{\sf{A.P=9,7,11,13.....}}}}}$

Step-by-step explanation:

$\huge{\pink{\boxed{\green{\underline{\red{\sf{SOLUTION-}}}}}}}$

${\pink{ \boxed{ \green{ \therefore an = 2n + 5}}}}$

☆ According to question:

☆ Take n = 1,2,3,4

$\to a1 = 2n + 5 \\ \to a1 = 2 \times 1 + 5 \\ \to a1 = 2 + 5 \\ {\boxed{\to a1 = 7}} \\ \\ \to a2 = 2 \times 2 + 5 \\ \to a2 = 4 + 5 \\ { \boxed{\to a2 = 9 }}\\ \\ \to a3 = 2 \times 3 + 5 \\ \to a3 = 6 + 5 \\ {\boxed{\to a3 = 11 }}\\ \\ \to common \: difference = a2 - a1 \\ \to d = 9 - 7 \\ {\boxed{\to d = 2}}$

$\huge{\pink{\boxed{\green{\sf{a=7}}}}}$

$\huge{\pink{\boxed{\green{\sf{d=2}}}}}$

$\huge{\pink{\boxed{\green{\sf{A.P=9,7,11,13.....}}}}}$

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