If `cosx/a=cos(x+theta)/b=cos(x+2theta)/c=cos(x+3theta)/d` then `(a+c)/(b+d)` is equal to `(A)a/d (B)c/d (C)b/c (D)d/a`

(cos x)/(a)=(cos(x+theta))/(b)=(cos(x+2 theta))/(c)=(cos(x+3 theta))/(d) then (a+c)/(b+d) is equal to (A)(a)/(d)(B)(c)/(d)(C)(b)/(c)(D)(d)/(a)

(cos x)/(a)=(cos(x+theta))/(b)=(cos(x+20))/(b)=(cos(x+3 theta))/(d) then (a+c)/(b+d) is equal to (a)(a)/(d) (b) (c)/(b)(c)(b)/(c)(d)(d)/(a)

If cos 5theta=a cos theta + b cos^(3)theta+c cos^(5) theta+d , then

cos5 theta=a cos theta+b cos^(3)theta+cos^(5)theta+d

If cos5 theta-a cos^(5)theta+b cos^(3)theta+c cos theta then c is equal to-

If a sin x+b cos(x+theta)+b cos(x-theta)=d then the minimum value of |cos theta| is equal to

If cos5 theta=a cos theta+b cos^(3)theta+c cos^(5)theta+d then the value of log _(d-b)(5ac) is equal to

If a sin x+b cos(x+theta)+b cos(x-theta)=d then the minimum value of |cos theta| is equal to (a) (1)/(2|b|)sqrt(d^(2)-a^(2))( b )(1)/(2|a|)sqrt(d^(2)-a^(2))(c)(1)/(2|d|)sqrt(d^(2)-a^(2))(d) none of these