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Consider the infinite series S=Σ(from n=0 to infinite) u(down n) where u(down n)=lim (from n π to (n+1) π) ((sin t)/t) dt. Explain why the series is alternating.

For the first part of the question we need to try and understand what is actually happening – we have the sum of an integral – where we are summing a sequence of definite integrals. So when n = 0 we have ...

Answered by Stuart D. • Maths tutor

5814 Views

Find an equation of the curve with parametric equations x=3sin(A) and y=4cos(A), in the form bx^2+cy^2=d.

x²=9sin²(A) and y²=16cos²(A)Since sin²(A)+cos²(A)=116x²+9y²=16 x 916x²+9y²=144

Answered by Pranav V. • Maths tutor

3523 Views

A shop sells only Apples, Bananas and Mangos. The ratio of Apples to Bananas is 5:11. The next shopper will choose one piece of fruit at random. The probability that they buy a Mango is 0.2. What is the probability that they buy an Apple?

We have the probability of choosing a Mango is 0.2 so the probability of choosing an Apple or Banana is 1-0.2=0.8.Next we use the ratio 5:11 to see that for every (5+11)=16 Apples or Bananas, 5 will be Ap...

Answered by Gregor M. • Maths tutor

3587 Views