if in a triangle ABC, angle B=90degree and AB:BC= 2:1 then find the values of the following a) tan A b) cos C c) sin A+ cot C
urgently please answer !!
Answers
Answer:
triangle ABC,∠B=90
∘
andAB:BC=2:1
\textbf{To find:}To find:
\textsf{The values of}The values of
\textsf{a) tanA b) cosC c) sinA+ cotC}a) tanA b) cosC c) sinA+ cotC
\textbf{Solution:}Solution:
\mathsf{Consider,}Consider,
\mathsf{AB:BC=2:1}AB:BC=2:1
\implie\mathsf{AB=2k\;\;\&\;\;BC=k}\implieAB=2k&BC=k
\textsf{By pythagoras theorem,}By pythagoras theorem,
\mathsf{AC^2=AB^2+BC^2}AC
2
=AB
2
+BC
2
\mathsf{AC^2=4k^2+k^2}AC
2
=4k
2
+k
2
\mathsf{AC^2=5k^2}AC
2
=5k
2
\mathsf{AC=\sqrt{5}k}AC=
5
k
\mathsf{Now,}Now,
\mathsf{tanA=\dfrac{BC}{AB}}tanA=
AB
BC
\mathsf{tanA=\dfrac{k}{2k}}tanA=
2k
k
\implies\boxed{\mathsf{tanA=\dfrac{1}{2}}}⟹
tanA=
2
1
\mathsf{cosC=\dfrac{BC}{AC}}cosC=
AC
BC
\mathsf{cosC=\dfrac{k}{\sqrt{5}k}}cosC=
5
k
k
\implies\boxed{\mathsf{cosC=\dfrac{1}{\sqrt{5}}}}⟹
cosC=
5
1
\mathsf{sinA+cotC}sinA+cotC