Ex 6A
13a)
b1/3=1/7 cube both sides, b=1/343
c)
x-3/4=27 both sides times to the power of -4/3 x=1/81
16c)
(2x3)x x (2x2)x divided by 3x/sup]=2^3x
d)
e), f) not going to bother, its straight forward after u can do one u can do them all
17d)
7^(n-1)(7+7^3)/7^(n-1)(1+7^2)=7
, e), f) there all the same....
Ex 6C
10b)Tn=3/32x 2^n Tn>10 3/32 x 2^n > 10 2^n>320/3 log2 320/3 < n 6.74... <n therefore first term greater than 10 is n=7
12a) T1=sin 90=1 T2=sin 180=0 T3=sin 270=-1 T4= 360=0 terms are zero when n is even
, c), e) same thing....
13a), b) just sub the terms in...
Ex 6D
5b)An = 2000 + 120n u can work see the common difference is 120.
, 7a) T1= 11 T2= 15 T3= 19 T4= 23 d=4 a= 11
Ex 6E
5c) how could u do the other ones and not get this one...
(T9/T4)1/4 = root2 = r T1= 6/root2^4 = 1.5 Tn=1.5xroot2^(n-1)
Ex 6F
3b)(27/8)^1/3=1.5 therefore 12 and 18
, c)(40-5)/10= common difference.
, d) same thing as b)
4b) (48/3)^1/4=2 a=6 b=12 c=24
5g)
Ex 6G
2a), f), c), h)
Ex 6H
6c)
Ex 6I
8e), f)
10a)
Ex 6J
5a)i)Tn=2^(n-1) T64= 2^63
, ii)Sn=(2^64-1)/(2-1)=2^64-1
, b)just divide by grains and cubic kilometres
Ex 6L
5e) 0.25+0.0057+0.000057+0.00000057.....=0.25+0.0057/(1-10^-2)=211/825
g)i dont get how u can do the other ones and not do some? they're all the same....unless u haven't done any of them at all
Ex 6N
6)
Ex 10B
9)y'=2x+a y'=2x+a = 0 when x=4 a=-8
Ex 10C
Q3d) as x--> infinity y=x as x--->-inifity y--->-x
, e) just draw it.
4b)asymptote y=1
, c)asymptote x=+-1 and y=1
, d)asymptote x=1 and y=1
those questions weren't that hard, i'm not really sure why u cudn't do them if u cud do the other ones unless u haven't done them as well...and u shud ask ur teacher for help as well, u dont hav to be scared