Q) A train travels a distance of 90 km at a constant speed. Had the speed been 15 km/h more, it would have taken 30 minutes less for the journey. Find the original speed of the train. Ans: Let’s consider the speed of the train is X km/hr. Now, to cover distance of 90 km, it […]
Q) The following table shows the ages of the patients admitted in a hospital during a year: Find the mode and mean of the data given above. Ans: (i) Mode value of the data: Since the modal class is the class with the highest frequency. In the given question, class “35 – 45” has 23
Q) Evaluate : 5 tan 60° / (sin2 60° + cos2 60°) tan 30° Ans: We know that: tan 600 = √ 3, sin 60 0 = , cos 600 = ; tan 300 = ; By submitting these values in the given expression, we get: = = = 5 √3 x √3 = 5
Evaluate : 5 tan 60° / (sin2 60° + cos2 60°) tan 30° Read More »
Q) In Δ ABC, if AD ⊥ BC and AD2 = BD x DC, then prove that ∠BAC = 900 Ans: Since AD ⊥ BC, ∴ ∠ ADB = ∠ ADC = 900 By Pythagoras theorem in Δ ADB, we get: AD2 + BD2 = AB2 ……………. (i) Similarly in Δ ADC, by Pythagoras theorem,
In Δ ABC, if AD ⊥ BC and AD2 = BD x DC, then prove that ∠BAC = 90° Read More »
Q) A man on a cliff observes a boat at an angle of depression of 30° which is approaching the shore to the point immediately beneath the observer with a uniform speed. Six minutes later, the angle of depression of the boat is found to be 60°. Find the time taken by the boat from
A man on a cliff observes a boat at an angle of depression of 30° which is approaching Read More »
Q) Prove that : (cosec θ – sin θ) (sec θ – cos θ) (tan θ + cot θ) = 1 Ans: Let’s start with LHS: LHS: (cosec θ – sin θ) (sec θ – cos θ) (tan θ + cot θ) = = = = = = 1 Please do press “Heart” button if you
Prove that : (cosec θ – sin θ) (sec θ – cos θ) (tan θ + cot θ) = 1 Read More »
Q) Evaluate : (sec2 450 – tan2 450)/sin2 450 Ans: We know that: sec 450 = , tan 450 = 1, sin 450 = ; By submitting these values in the given expression, we get: = = = 1 x 2 = 2 Hence the value of the given function is 2. Please do press “Heart”
Evaluate : (sec2 45° – tan2 45°)/sin2 45° Read More »
Q) Find the length of the median AD of Δ ABC having vertices A(0, –1), B(2, 1) and C(0, 3). Ans: Let’s plot the points on the graph: Step 1: Let’s understand the layout: If AD is median, it means D lies on line segment BC, and BD = CD Let the coordinates of point D
Find the length of the median AD of Δ ABC having vertices A(0, –1), B(2, 1) and C(0, 3). Read More »
Q) In what ratio does the X-axis divide the line segment joining the points(2, – 3) and (5, 6)? Also, find the coordinates of the point of intersection. Ans: Let’s draw the diagram to solve: (i) Ratio of division: We know that the value of y-coordinate on X- axis is always 0 It is given
Q) Prove that Ans: Let’s start solving from LHS: = = = = = ∵ sin2 A + cos2 A = 1, ∴ cos2 A = 1 – sin2 A ∴ LHS = = = = RHS…. Hence Proved ! Please press the “Heart”, if you like the solution.