Analysis and Approaches for IBDP Maths Ebook 2 | Page 57

3. (a) Using the extended binomial expansion, find the terms of the expansion
9x
2
of
in ascending powers of x up to x .
(3 �x)(6 �x)
(b)
Hence, state the range of values of x for this binomial expansion to be valid.
[7]
[2]
1�
5x
4. In the expansion of
2
(3 � kx)
value of k .
, the coefficient of
2
x is
37
� , where 0 �k
� 10 . Find the
27
[8]
4
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