Write down the first 4 terms in the expansion of (1+2x)^7

1 + 14x + 84x^2 + 280x^3 or

128x^7 + 448x^6 + 672x^5 + 560x^4.

(see explanation),

Step-by-step explanation:

They are 1^7 + 7C1 1^(7-1)(2x) + 7C2 1^5 (2x)^2 + 7C3 1^4 (2x)^3

= 1 + 14x + 21* 4x^2 + 35*8x^3

= 1 + 14x + 84x^2 + 280x^3

If you require the answer in descending degrees of x by a similar method the answer is:

128x^7 + 448x^6 + 672x^5 + 560x^4.

distance covered by pamela in 9 l of fuel = 99km

let us apply unitary method here.

distance covered by pamela in 1 l of fuel =99/9 =11 km

now let us find distance covered by pamela if she has 12 l of fuel.

distance covered in 12 l = distance covered in 1 l of fuel * 12

we know that distance covered by here in 1 l is 11 km.

so distance covered in 12 l of fuel = 11*12 = 132 km.

answer:

what is your question that you ask

step-by-step explanation: