Page 135 - Math SL HB Sem 1

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ll . fMa:nnun nork ]ll

(n) Consider the equatroD 4_rr + tr + I = 0 - For rthat values of t does tfiis equation
have tw,-o equal roots?
,
hnl L.*r-4 [i markJ
Let / be the firrrctron f@)=2cos20+4cos0+3,for -360.<6<360._

(b) Shoru tlrat this fuuctroa may be r.vritteo as (0)
_f = 4ca1sl 0+qcosB+1, [] norkl

(.) Corsrder rhe eqrration
;t(B) = 0. for _360. <B < 160.
h^s:l
(, How mary dishlct values of cosB satis$ rfiis equatioa?
t1l. 0 - 2y o ,la,o ,- yt4
_i>-n
(,D Fiud all rzlues of 6 nhiclr satisfy this equatiou.
[5 markJ
Gl) (itl'en that
[) markJ
/(d) =c is satrsfied by ooly dree values of 0, frd the value of c
Ant' ( q

r3, Y&S