The Tₙ of the sequence 1, 3, 9, … is:
The acute angle θ for which sin θ, 2 cos θ, and 2 sin θ are the first three terms of an AP is:
Which term of the A.P. 121, 117, 113, … is the first negative term?
The sum of the first n terms of a sequence is given by Sₙ = n² + 2n. Then the expression for Tₙ is:
How many terms of the series −8, −6, −4, … make the sum 907?
