Download App

T-Ratios of Some Particular Angles — Maths STD 10 — Question

CBSE BoardEnglish MediumSTD 10MathsT-Ratios of Some Particular Angles5 Marks
Question
Evaluate the following:
In the adjoining figure, $\triangle\text{ABC}$ is a right-angled at B and $\angle\text{A}=45^\circ,$ If $\text{AC}=3\sqrt{2}\text{cm},$
Find:
  1. BC.
  2. AB.
✓

Answer

From the given right-angled $\triangle\text{ABC},$ we have:
$\frac{\text{BC}}{\text{AC}}=\sin45^\circ$
$\Rightarrow\frac{\text{BC}}{3\sqrt{2}}=\frac{1}{\sqrt{2}}$
$\Rightarrow\text{BC}=3\text{cm}$
Also, $\frac{\text{AB}}{\text{AC}}=\cos45^\circ$
$\Rightarrow\frac{\text{AB}}{3\sqrt{2}}=\frac{1}{\sqrt{2}}$
$\Rightarrow\text{AB}=3\text{cm}$
$\therefore\ \text{BC}=3\text{cm}$ and $\text{AC}=3\text{cm}$

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free

Explore more

More "5 Marks Questions" from T-Ratios of Some Particular Angles→T-Ratios of Some Particular Angles — all question types→Maths STD 10 question papers→CBSE Board STD 10 question papers→CBSE Board question paper generator→

Similar questions

It is given that -1 is one of the zeros of the polynomial $x^3 + 2x^2 - 11x - 12$. Find all the given zeros of the given polynomial.
→
Prove the following identities:
$\frac{\sin\theta-\cos\theta}{\sin\theta+\cos\theta}+\frac{\sin\theta+\cos\theta}{\sin\theta-\cos\theta}=\frac{2}{\big(2\sin^2\theta-1\big)}$
→
Find the roots of the following equations, if they exist, by applying the quadratic formula:$\text{x}-\frac{1}{\text{x}}=3,\ \text{x}\neq0$
→
In a right triangle ABC in which $\angle\text{B}=90^\circ,$ a circle is drawn with AB as diameter intersecting the hypotenuse AC and P. Prove that the tangent to the circle at P bisects BC.
→
In an AP: $a_3=15, S_{10}=125$, find $d$ and $a_{10}$.
→
In the adjoining figure, ABC is a triangle in which AB = AC. If D and E are points on AB and AC respectively such that AD = AE, show that the points B, C, E and D are concyclic.
→
Construct an isosceles triangle whose base is 9cm and altitude 5cm. Construct another triangle whose side are $\frac34$ of the corresponding sides of the first isosceles triangle.
→
Prove that the points (4, 5) (7, 6), (6, 3), (3, 2) are the vertices of a parallelogram. Is it a rectangle.
→
Prove that $\frac{\sin\text{A}-2\sin^3\text{A}}{\big(2\cos^2\text{A}-\cos\text{A}\big)}=\tan\text{A}.$
→
Two dice are rolled together. Find the probability of getting such numbers on two dice whose product is a perfect square.
→