10. Find the first terms and common difference of an AP, whose t8=3 andt12=52 About the author Amaya
Answer: The first term is -331/4 The common difference is 49/4 Step-by-step explanation: t8 =3 and t12=52 t8 = a + 7d = 3 –(1) t12 = a + 11d = 52 –(2) from eq.–(1) a + 7d = 3 a = 3 – 7d–(3) Put value of a in eq.–(2) 3 – 7d + 11d = 52 4d = 52 – 3 4d = 49 d = 49/4 Now put d in eq.–(3) a = 3 – 7(49/4) = (12 – 343)/4 = -331/4 Reply
Answer:
The first term is -331/4
The common difference is 49/4
Step-by-step explanation:
t8 =3 and
t12=52
t8 = a + 7d = 3 –(1)
t12 = a + 11d = 52 –(2)
from eq.–(1)
a + 7d = 3
a = 3 – 7d–(3)
Put value of a in eq.–(2)
3 – 7d + 11d = 52
4d = 52 – 3
4d = 49
d = 49/4
Now put d in eq.–(3)
a = 3 – 7(49/4)
= (12 – 343)/4
= -331/4