NIMCET 2025 — Mathematics PYQ
NIMCET | Mathematics | 2025The slope of the normal line to the curve x=t2+3t−8 and y=2t2−2t−5 at the point (2,−1) is:
Choose the correct answer:
- A.
722
- B.
-5
- C.
−76
- D.
−67
−67
Explanation
Solution
Step 1: Solve for t
At (2,−1):
x=t2+3t−8=2⟹t2+3t−10=0⟹(t+5)(t−2)=0
y=2t2−2t−5=−1⟹2t2−2t−4=0⟹t2−t−2=0⟹(t−2)(t+1)=0
Common value is t=2.
Step 2: Find Derivatives
dtdx=2t+3
dtdy=4t−2
Step 3: Slope of Tangent (mt)
At t=2:
dtdx=2(2)+3=7
dtdy=4(2)−2=6
mt=dx/dtdy/dt=76
Step 4: Slope of Normal (mn)
mn=−mt1=−67
Final Answer:
The slope of the normal is −67. (Option D)
Explanation
Solution
Step 1: Solve for t
At (2,−1):
x=t2+3t−8=2⟹t2+3t−10=0⟹(t+5)(t−2)=0
y=2t2−2t−5=−1⟹2t2−2t−4=0⟹t2−t−2=0⟹(t−2)(t+1)=0
Common value is t=2.
Step 2: Find Derivatives
dtdx=2t+3
dtdy=4t−2
Step 3: Slope of Tangent (mt)
At t=2:
dtdx=2(2)+3=7
dtdy=4(2)−2=6
mt=dx/dtdy/dt=76
Step 4: Slope of Normal (mn)
mn=−mt1=−67
Final Answer:
The slope of the normal is −67. (Option D)

