1.The first three terms of the expansion of (1+kx)^n are 1+6x+27x^2. Find k and n and hence find the term in x^3.
2.In the expansion of (1+ax)^n, in ascending powers of x, the coefficient of x is 12 and the coefficient of x^3 is six times the coefficient of x^2. Find a and n.
3.Find dy/dx in terms of x and y: 2sin2xcos3y=1
Could anyone help me with the above questions. Thanks
Hello again, Confuzzled!
1.The first three terms of the expansion of are: .
Find and and hence find the coefficient of
Binomial Theorem: .
Hence, we have: .[1] .and [2] .
[1] becomes: . [3]
[2] becomes: . [4]
Divide [4] by [3]: .
Divide by [3]: .
Solve for
Substitute into [3]: .
Then: . . . . coefficient of
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