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What is the coefficient of x^4 in the expansion of (x+3)^7

Start by expanding (a+b)⁷, using Pascal's Triangle or the binomial coefficient function to work out the coefficients:a⁷ + 7a⁶b + 21a⁵b² + 35a⁴

Answered by Josef W. • Maths tutor

8278 Views

Integrate 1/(1 - 3*x) with respect to x

First substitute: u = 1 - 3xNext calculate: du/dx = -3 .... therefore dx = (-1/3) * duNow re-arrange the expression: Integrate 1/u * ( -1/3)*duNext recall the integral of 1/x is the natural logarithm, and...

Answered by Neil M. • Maths tutor

3343 Views

How do you analyse a poem?

Writing a good, coherent poem analysis is often seen as very hard, but once you understand and have good knowledge of all the parts that make up a poem, you will see how smooth and enjoyable this process ...

Answered by Anna R. • English tutor

1712 Views

If, f(x) = 8x^3 + 1 / x^3 . Find f''(x).

f(x) = 8x³ + 1 / x³ >>> f(x) = 8x³ + x^-3
f'(x) = 3(8x² ) + -3(x^-4) >>> f'(x) = 24...

Answered by Sam S. • Maths tutor

4737 Views

Explain the importance of accessory pigments in photosynthesis.

Accessory pigments, such as carotenoids and xanthrophylls, increase the rate of photosynthesis by increasing the efficiency of light absorption in both photosystem I and II, specifically in the light harv...

Answered by Finley W. • Biology tutor

21186 Views