Question

Find the 20 term of the AP whose 3 term is 7 and the 7 term exceed three times the 3
term by 2.
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Answer 1

Answer:

The 20th term of the AP is 75.

Step-by-step explanation:

The nth term of an AP is:

$T_{n}=a+(n-1)d$

It is provided that:

$T_{3}=7\\T_{7}=3T_{3}+2$

Substitute the value of T₃ in T₇ and solve as follows:

$T_{7}=3T_{3}+2\\a+(7-1)d=3(a+(3-1)d)+2\\a+6d=3a+6d+2\\a=3a+2\\-2a=2\\a=-1$

Compute the value of d as follows:

$T_{3}=7\\a+(3-1)d=7\\-1+2d=7\\2d=8\\d=4$

Compute the 20th term as follows:

$T_{20}=-1+(20-1)\times4=-1+76=75$

Thus, the 20th term of the AP is 75.

Answer 2

Answer:

SorryI don't know but koi tumhari help kardega byy