If r is real number such that |r|<1 and if a=5(1–r), then
–5<a<5
0<a<10
0<a<5
-10<a<10
Explanation for the correct option:
Finding the range of a.
It is given that, |r|<1,
⇒-1<r<1[∵a<1⇒-1<a<1]⇒1>-r>-1⇒-1<-r<1
By adding 1, we get
⇒0<1-r<2
By multiplying by 5, we get
⇒0<51-r<10⇒0<a<10
Therefore, the correct answer is option B.
If r is a real number that r<1 and if a=51-r, then
Let z be a complex number such that ∣∣∣z+1z∣∣∣=2.
If |z|=r1 and r2 for argz=π4 then
|r1−r2|=
arg z varies |r1−r2|=
If x is a real number and p,q,rare whole numbers, then prove that xpxqp+q×xrxpr+p×xqxrq+r=1